类别：程序开发
日期：2022-05-10 浏览：2048 评论：0
Python由荷兰数学和计算机科学研究学会的吉多·范罗苏姆 于1990 年代初设计，作为一门叫做ABC语言的替代品。 [1] Python提供了高效的高级数据结构，还能简单有效地面向对象编程。Python语法和动态类型，以及解释型语言的本质，使它成为多数平台上写脚本和快速开发应用的编程语言， [2] 随着版本的不断更新和语言新功能的添加，逐渐被用于独立的、大型项目的开发。
一、变量赋值及命名规则
① 声明一个变量及赋值
#!/usr/bin/env python # -*- coding:utf-8 -*- # _author_soloLi name1="solo" name2=name1 print(name1,name2) name1 = "hehe" print(name1,name2)
#name1的值为hehe，name2的值为solo
② 变量命名的规则
1、变量名只能是 字母、数字或下划线的任意组合 2、变量名的第一个字符不能是数字 3、以下关键字不能声明为变量名['and', 'as', 'assert', 'break', 'class', 'continue', 'def', 'del', 'elif', 'else', 'except', 'exec', 'finally', 'for', 'from', 'global','if', 'import', 'in', 'is', 'lambda', 'not', 'or', 'pass', 'print', 'raise', 'return', 'try', 'while', 'with', 'yield']
二、字符编码
python解释器在加载 .py 文件中的代码时，会对内容进行编码（默认ascill）
ASCII：最多只能用 8位来表示（一个字节），即：2**8 = 256，所以，ASCII码最多只能表示 256 个符号。显然ASCII码无法将世界上的各种文字和符号全部表示。
Unicode：它为每种语言中的每个字符设定了统一并且唯一的二进制编码，规定虽有的字符和符号最少由 16 位来表示（2个字节），即：2 **16 = 65536，注：此处说的的是最少2个字节，可能更多。
UTF-8：是对Unicode编码的压缩和优化，他不再使用最少使用2个字节，而是将所有的字符和符号进行分类：ascii码中的内容用1个字节保存、欧洲的字符用2个字节保存，东亚的字符用3个字节保存...
注：python2.x版本，默认支持的字符编码为ASCll python3.x版本，默认支持的是Unicode，不用声明字符编码可以直接显示中文。
扩展：字符编码和转码，bytes和str区别
Python 3最重要的新特性大概要算是对文本和二进制数据作了更为清晰的区分。文本总是Unicode，由str类型表示，二进制数据则由bytes类型表示。Python 3不会以任意隐式的方式混用str和bytes（类似int和long之间自动转换），正是这使得两者的区分特别清晰。你不能拼接字符串和字节包，也无法在字节包里搜索字符串（反之亦然），也不能将字符串传入参数为字节包的函数（反之亦然）。这是件好事。不管怎样，字符串和字节包之间的界线是必然的，下面的图解非常重要，务请牢记于心：
字符串可以编码成字节包，而字节包可以解码成字符串：
#!/usr/bin/env python
# -*- coding:utf-8 -*-
#-Author-solo
msg = "里约奥运"
print(msg.encode("utf-8")) #如果不指定编码格式，默认为utf-8
#b'\xe9\x87\x8c\xe7\xba\xa6\xe5\xa5\xa5\xe8\xbf\x90'
print(b'\xe9\x87\x8c\xe7\xba\xa6\xe5\xa5\xa5\xe8\xbf\x90'.decode("utf-8"))
#里约奥运
为什么要进行编码和转码？
由于每个国家电脑的字符编码格式不统一（列中国：GBK），同一款软件放到不同国家的电脑上会出现乱码的情况，出现这种情况如何解决呢？！ 当然由于所有国家的电脑都支持Unicode万国码，那么我们可以把Unicode为跳板，先把字符编码转换为Unicode，在把Unicode转换为另一个国家的字符编码（例韩国），则不会出现乱码的情况。当然这里只是转编码集并不是翻译成韩文不要弄混了。
① Python3.0进行编码转换（默认Unicode编码）
name = "李伟" #此时name为Unicode编码
name1 = name.encode("utf-8") #Unicode转为UTF-8
name2 = name1.decode("utf-8") #UTF-8转为Unicode
name3 = name.encode("gbk") #Unicode转为GBK
name4 = name3.decode("gbk") #GBK转为Unicode
② Python2.0中的编码转换（默认ascii编码）
① 声明字符编码（utf-8）
# -*- coding:utf-8 -*-
name = "李伟" #ascii码里是没有字符“你好”的，此时的name为uft-8
name1 = name.decode("utf-8") #UTF-8转为Unicode
name2 = name1.encode("gbk") #Unicode转为gbk
② 使用默认字符编码（ascii）
name = "nihao" #英文字符，且第二行字符声明去掉，此刻name为ascii码
name1 = name.decode("ascii") #ascii码转为unicode
name2 = name1.encode("utf-8") #unicode转为utf-8
name3 =name1.encode("gbk") #unicode转为gbk
三、用户交互及字符串拼接
#!/usr/bin/env python
# -*- coding:utf-8 -*-
# _author_soloLi
# python2.X与python3.X区别: python2.X raw_input = python3.X input
# 提示用户输入姓名、年龄、工作、工资并以信息列表的形式打印出
name = input("Please input your name:")
age = int(input("Please input your age:")) #str强制转换为int
job = input("Please input your job:")
salary = input("Please input your salary:")
info1 = '''
------------ Info of %s ---------
Name:%s
Age:%d
Job：%s
Salary：%s
''' %(name,name,age,job,salary) #%s检测数据类型为字符串，%d检测数据类型为整数,%f检测数据类型为浮点数 强制
print(info1)
# info2 = '''
# ------------ Info of {_Name} ---------
# Name:{_Name}
# Age:{_Age}
# Job：{_Job}
# Salary：{_Salary}
# ''' .format(_Name=name,
# _Age=age,
# _Job=job,
# _Salary=salary)
# print(info2)
# info3 = '''
# ------------ Info of {0} ---------
# Name:{0}
# Age:{1}
# Job：{2}
# Salary：{3}
# ''' .format(name,age,job,salary)
# print(info3)
对比分析：
1、% ：无法同时传递一个变量和元组，又是要加（）来保证不抛出typeerror异常
2、+ ：每增加一个一个+就会开辟一块新的内存空间
3、.fomat ：不会出现上述问题，有时使用为了兼容Python2版本。如使用logging库
四、循环语句（if、while、for、三元运算）
#!/usr/bin/env python
# -*- coding:utf-8 -*-
# _author_soloLi
################## if语句 ######################
# A = 66
#
# B = int(input("请输入0-100的幸运数字:"))
#
# if B == A: #母级顶格写
# print ("恭喜你猜对了!") #子级强制缩进写
# elif B > A :
# print ("猜小了")
# else:
# print ("猜大了")
################## while语句 ######################
# A = 66
# count = 0 # 设置初始值count=0
#
# while count < 3 :
#
# B = int(input("请输入0-100的数字:"))
#
# if B == A:
# print ("恭喜你猜对了!")
# break
# elif B > A :
# print ("猜大了")
# else:
# print ("猜小了")
# count += 1
# else:
# print ("你猜的次数太多了!")
################## for语句 ######################
A = 66
i=1
for i in range(3):# while判断count是否小于3，如果小于3则：
print("i=",i)
B = int(input("请输入0-100的数字:"))
if B == A:
print ("恭喜你猜对了!")
break
elif B > A :
print ("猜小了")
else:
print ("猜大了")
i+=1
else:
print ("你猜的次数太多了!")
################## 三元运算 ######################
# esult = 值1 if 条件 else 值2
# 如果条件成立，那么将 “值1” 赋值给result变量，否则，将“值2”赋值给result变量
五、基本数据类型
# ①数字 # 1.整型int # 作用：年纪，等级，身份证号，qq号等整型数字相关 # 2.浮点型float # 作用：薪资，身高，体重，体质参数等浮点数相关 # 3.长整形 # python3中没有长整形的概念 # 进制的转换：bin(转成二进制)、oct(转成八进制)、hex(转成十六进制) # # ②字符串 # 作用：名字，性别，国籍，地址等描述信息 # 常用操作：1.移除空白： strip （参数1：移除什么符号） # 2.切分： split （参数1：以什么符号进行切割，参数2：最大切割次数） 切割成列表 # 3.长度： len 统计的字符的长度 # 4.切片： [] （参数1：起始位置：参数2：步长） 顾头不顾尾 # 5.替换： replace（参数1：old，参数2：new，参数3：替换第几个） # 6.拼接： format # 7.索引： 只能取 # 8.判断开头或结尾： startswith,endswith # 9.其他。。。 # # ③列表 # 作用：多个装备，多个爱好，多门课程，多个女朋友等 # 常用操作：1.索引： 即可存也可以取 # 2.切片： [] 切成新的列表 # 3.追加： append # 4.删除： remove（按照值）/pop（按照索引） # 5.长度： len 统计的列表的元素个数 # 6.成员运算（包含）:in # 7.循环： # 8.插入： insert # 9.其他。。。 # # ④元组 # 作用：存多个值，对比列表来说，元组不可变，主要是用来读 # 常用操作：除了不能改变元组的之外，其他操作跟列表相同 # 1.索引： index只能取 # 2.切片： [] # 3.长度： len # 4.循环： # 5.成员运算（包含）:in # 6.统计： count # # ⑤字典 # 作用：存多个值,key-value(键值对)存取，取值速度快 # 常用操作：1.按key存取值：可存可取 # 2.循环: 无序 # 3.长度： len # 4.删除： pop 第2个参数设置none 程序即使取不到值也不报错 # 5.成员运算（包含）:in # 6.取值： get（不存在程序不报错）/info（不存在程序报错） # 7.其他。。。 # # ⑥集合 # 作用：去重，关系运算， # 常用操作：1.长度： len # 2.添加： add（只能添加一个元素）/update（可以添加多个元素） # 3.删除： remove（删除指定元素）/pop（随机删除元素）/discard（删除指定元素，与remove区别在于，如果元素不存在也不会报错） # 4.交集： & # 5.差集： - # 6.对称差集： ^ # 7.成员运算： in # 8.合集： | # 9.父集： >,>= # 10.子集： <,<= # # 小结： # 按存值个数区分 # 标量／原子类型:数字，字符串 # 容器类型:列表，元组，字典 # # 按可变不可变区分 # 可变:列表，字典 # 不可变:数字，字符串，元组 # # 按访问方式区分 # 直接访问：数字 # 按照索引访问（序列类型）：字符串，列表，元组 # key访问（映射类型） 字典 【总结】常见的数据类型有哪些？主要操作方法有哪些？
一、整型
如： 18、73、84
类型常用功能：
abs(x) #返回绝对值 x+y,x-y,x*y,x/y #加减乘除 x/y #取商，浮点数相除保留余数 x//y #取商，浮点数相除余数为0 x%y #取余 x**y #幂次方 cmp(x,y) #两个数比较，返回True或False相等则为0 coerce(x,y) #强制把两个数生成一个元组 divmod(x,y) #相除得到商和余数组成的元组 float(x) #转换为浮点型 str(x) #转换为字符串 hex(x) #转换为16进制 oct(x) #转换8进制
更多功能：
class int(object):
"""
int(x=0) -> int or long
int(x, base=10) -> int or long
Convert a number or string to an integer, or return 0 if no arguments
are given. If x is floating point, the conversion truncates towards zero.
If x is outside the integer range, the function returns a long instead.
If x is not a number or if base is given, then x must be a string or
Unicode object representing an integer literal in the given base. The
literal can be preceded by '+' or '-' and be surrounded by whitespace.
The base defaults to 10. Valid bases are 0 and 2-36. Base 0 means to
interpret the base from the string as an integer literal.
>>> int('0b100', base=0)
"""
def bit_length(self):
""" 返回表示该数字的时占用的最少位数 """
"""
int.bit_length() -> int
Number of bits necessary to represent self in binary.
>>> bin(37)
'0b100101'
>>> (37).bit_length()
"""
return 0
def conjugate(self, *args, **kwargs): # real signature unknown
""" 返回该复数的共轭复数 """
""" Returns self, the complex conjugate of any int. """
pass
def __abs__(self):
""" 返回绝对值 """
""" x.__abs__() <==> abs(x) """
pass
def __add__(self, y):
""" x.__add__(y) <==> x+y """
pass
def __and__(self, y):
""" x.__and__(y) <==> x&y """
pass
def __cmp__(self, y):
""" 比较两个数大小 """
""" x.__cmp__(y) <==> cmp(x,y) """
pass
def __coerce__(self, y):
""" 强制生成一个元组 """
""" x.__coerce__(y) <==> coerce(x, y) """
pass
def __divmod__(self, y):
""" 相除，得到商和余数组成的元组 """
""" x.__divmod__(y) <==> divmod(x, y) """
pass
def __div__(self, y):
""" x.__div__(y) <==> x/y """
pass
def __float__(self):
""" 转换为浮点类型 """
""" x.__float__() <==> float(x) """
pass
def __floordiv__(self, y):
""" x.__floordiv__(y) <==> x//y """
pass
def __format__(self, *args, **kwargs): # real signature unknown
pass
def __getattribute__(self, name):
""" x.__getattribute__('name') <==> x.name """
pass
def __getnewargs__(self, *args, **kwargs): # real signature unknown
""" 内部调用 __new__方法或创建对象时传入参数使用 """
pass
def __hash__(self):
"""如果对象object为哈希表类型，返回对象object的哈希值。哈希值为整数。在字典查找中，哈希值用于快速比较字典的键。两个数值如果相等，则哈希值也相等。"""
""" x.__hash__() <==> hash(x) """
pass
def __hex__(self):
""" 返回当前数的 十六进制 表示 """
""" x.__hex__() <==> hex(x) """
pass
def __index__(self):
""" 用于切片，数字无意义 """
""" x[y:z] <==> x[y.__index__():z.__index__()] """
pass
def __init__(self, x, base=10): # known special case of int.__init__
""" 构造方法，执行 x = 123 或 x = int(10) 时，自动调用，暂时忽略 """
"""
int(x=0) -> int or long
int(x, base=10) -> int or long
Convert a number or string to an integer, or return 0 if no arguments
are given. If x is floating point, the conversion truncates towards zero.
If x is outside the integer range, the function returns a long instead.
If x is not a number or if base is given, then x must be a string or
Unicode object representing an integer literal in the given base. The
literal can be preceded by '+' or '-' and be surrounded by whitespace.
The base defaults to 10. Valid bases are 0 and 2-36. Base 0 means to
interpret the base from the string as an integer literal.
>>> int('0b100', base=0)
# (copied from class doc)
"""
pass
def __int__(self):
""" 转换为整数 """
""" x.__int__() <==> int(x) """
pass
def __invert__(self):
""" x.__invert__() <==> ~x """
pass
def __long__(self):
""" 转换为长整数 """
""" x.__long__() <==> long(x) """
pass
def __lshift__(self, y):
""" x.__lshift__(y) <==> x<<y """
pass
def __mod__(self, y):
""" x.__mod__(y) <==> x%y """
pass
def __mul__(self, y):
""" x.__mul__(y) <==> x*y """
pass
def __neg__(self):
""" x.__neg__() <==> -x """
pass
@staticmethod # known case of __new__
def __new__(S, *more):
""" T.__new__(S, ...) -> a new object with type S, a subtype of T """
pass
def __nonzero__(self):
""" x.__nonzero__() <==> x != 0 """
pass
def __oct__(self):
""" 返回改值的 八进制 表示 """
""" x.__oct__() <==> oct(x) """
pass
def __or__(self, y):
""" x.__or__(y) <==> x|y """
pass
def __pos__(self):
""" x.__pos__() <==> +x """
pass
def __pow__(self, y, z=None):
""" 幂，次方 """
""" x.__pow__(y[, z]) <==> pow(x, y[, z]) """
pass
def __radd__(self, y):
""" x.__radd__(y) <==> y+x """
pass
def __rand__(self, y):
""" x.__rand__(y) <==> y&x """
pass
def __rdivmod__(self, y):
""" x.__rdivmod__(y) <==> divmod(y, x) """
pass
def __rdiv__(self, y):
""" x.__rdiv__(y) <==> y/x """
pass
def __repr__(self):
"""转化为解释器可读取的形式 """
""" x.__repr__() <==> repr(x) """
pass
def __str__(self):
"""转换为人阅读的形式，如果没有适于人阅读的解释形式的话，则返回解释器课阅读的形式"""
""" x.__str__() <==> str(x) """
pass
def __rfloordiv__(self, y):
""" x.__rfloordiv__(y) <==> y//x """
pass
def __rlshift__(self, y):
""" x.__rlshift__(y) <==> y<<x """
pass
def __rmod__(self, y):
""" x.__rmod__(y) <==> y%x """
pass
def __rmul__(self, y):
""" x.__rmul__(y) <==> y*x """
pass
def __ror__(self, y):
""" x.__ror__(y) <==> y|x """
pass
def __rpow__(self, x, z=None):
""" y.__rpow__(x[, z]) <==> pow(x, y[, z]) """
pass
def __rrshift__(self, y):
""" x.__rrshift__(y) <==> y>>x """
pass
def __rshift__(self, y):
""" x.__rshift__(y) <==> x>>y """
pass
def __rsub__(self, y):
""" x.__rsub__(y) <==> y-x """
pass
def __rtruediv__(self, y):
""" x.__rtruediv__(y) <==> y/x """
pass
def __rxor__(self, y):
""" x.__rxor__(y) <==> y^x """
pass
def __sub__(self, y):
""" x.__sub__(y) <==> x-y """
pass
def __truediv__(self, y):
""" x.__truediv__(y) <==> x/y """
pass
def __trunc__(self, *args, **kwargs):
""" 返回数值被截取为整形的值，在整形中无意义 """
pass
def __xor__(self, y):
""" x.__xor__(y) <==> x^y """
pass
denominator = property(lambda self: object(), lambda self, v: None, lambda self: None) # default
""" 分母 = 1 """
"""the denominator of a rational number in lowest terms"""
imag = property(lambda self: object(), lambda self, v: None, lambda self: None) # default
""" 虚数，无意义 """
"""the imaginary part of a complex number"""
numerator = property(lambda self: object(), lambda self, v: None, lambda self: None) # default
""" 分子 = 数字大小 """
"""the numerator of a rational number in lowest terms"""
real = property(lambda self: object(), lambda self, v: None, lambda self: None) # default
""" 实属，无意义 """
"""the real part of a complex number"""
int
int
二、长整型
如：2147483649、9223372036854775807
类型常用功能：
1 #长整型功能与整形基本类似
更多功能：
class long(object):
"""
long(x=0) -> long
long(x, base=10) -> long
Convert a number or string to a long integer, or return 0L if no arguments
are given. If x is floating point, the conversion truncates towards zero.
If x is not a number or if base is given, then x must be a string or
Unicode object representing an integer literal in the given base. The
literal can be preceded by '+' or '-' and be surrounded by whitespace.
The base defaults to 10. Valid bases are 0 and 2-36. Base 0 means to
interpret the base from the string as an integer literal.
>>> int('0b100', base=0)
4L
"""
def bit_length(self): # real signature unknown; restored from __doc__
"""
long.bit_length() -> int or long
Number of bits necessary to represent self in binary.
>>> bin(37L)
'0b100101'
>>> (37L).bit_length()
"""
return 0
def conjugate(self, *args, **kwargs): # real signature unknown
""" Returns self, the complex conjugate of any long. """
pass
def __abs__(self): # real signature unknown; restored from __doc__
""" x.__abs__() <==> abs(x) """
pass
def __add__(self, y): # real signature unknown; restored from __doc__
""" x.__add__(y) <==> x+y """
pass
def __and__(self, y): # real signature unknown; restored from __doc__
""" x.__and__(y) <==> x&y """
pass
def __cmp__(self, y): # real signature unknown; restored from __doc__
""" x.__cmp__(y) <==> cmp(x,y) """
pass
def __coerce__(self, y): # real signature unknown; restored from __doc__
""" x.__coerce__(y) <==> coerce(x, y) """
pass
def __divmod__(self, y): # real signature unknown; restored from __doc__
""" x.__divmod__(y) <==> divmod(x, y) """
pass
def __div__(self, y): # real signature unknown; restored from __doc__
""" x.__div__(y) <==> x/y """
pass
def __float__(self): # real signature unknown; restored from __doc__
""" x.__float__() <==> float(x) """
pass
def __floordiv__(self, y): # real signature unknown; restored from __doc__
""" x.__floordiv__(y) <==> x//y """
pass
def __format__(self, *args, **kwargs): # real signature unknown
pass
def __getattribute__(self, name): # real signature unknown; restored from __doc__
""" x.__getattribute__('name') <==> x.name """
pass
def __getnewargs__(self, *args, **kwargs): # real signature unknown
pass
def __hash__(self): # real signature unknown; restored from __doc__
""" x.__hash__() <==> hash(x) """
pass
def __hex__(self): # real signature unknown; restored from __doc__
""" x.__hex__() <==> hex(x) """
pass
def __index__(self): # real signature unknown; restored from __doc__
""" x[y:z] <==> x[y.__index__():z.__index__()] """
pass
def __init__(self, x=0): # real signature unknown; restored from __doc__
pass
def __int__(self): # real signature unknown; restored from __doc__
""" x.__int__() <==> int(x) """
pass
def __invert__(self): # real signature unknown; restored from __doc__
""" x.__invert__() <==> ~x """
pass
def __long__(self): # real signature unknown; restored from __doc__
""" x.__long__() <==> long(x) """
pass
def __lshift__(self, y): # real signature unknown; restored from __doc__
""" x.__lshift__(y) <==> x<<y """
pass
def __mod__(self, y): # real signature unknown; restored from __doc__
""" x.__mod__(y) <==> x%y """
pass
def __mul__(self, y): # real signature unknown; restored from __doc__
""" x.__mul__(y) <==> x*y """
pass
def __neg__(self): # real signature unknown; restored from __doc__
""" x.__neg__() <==> -x """
pass
@staticmethod # known case of __new__
def __new__(S, *more): # real signature unknown; restored from __doc__
""" T.__new__(S, ...) -> a new object with type S, a subtype of T """
pass
def __nonzero__(self): # real signature unknown; restored from __doc__
""" x.__nonzero__() <==> x != 0 """
pass
def __oct__(self): # real signature unknown; restored from __doc__
""" x.__oct__() <==> oct(x) """
pass
def __or__(self, y): # real signature unknown; restored from __doc__
""" x.__or__(y) <==> x|y """
pass
def __pos__(self): # real signature unknown; restored from __doc__
""" x.__pos__() <==> +x """
pass
def __pow__(self, y, z=None): # real signature unknown; restored from __doc__
""" x.__pow__(y[, z]) <==> pow(x, y[, z]) """
pass
def __radd__(self, y): # real signature unknown; restored from __doc__
""" x.__radd__(y) <==> y+x """
pass
def __rand__(self, y): # real signature unknown; restored from __doc__
""" x.__rand__(y) <==> y&x """
pass
def __rdivmod__(self, y): # real signature unknown; restored from __doc__
""" x.__rdivmod__(y) <==> divmod(y, x) """
pass
def __rdiv__(self, y): # real signature unknown; restored from __doc__
""" x.__rdiv__(y) <==> y/x """
pass
def __repr__(self): # real signature unknown; restored from __doc__
""" x.__repr__() <==> repr(x) """
pass
def __rfloordiv__(self, y): # real signature unknown; restored from __doc__
""" x.__rfloordiv__(y) <==> y//x """
pass
def __rlshift__(self, y): # real signature unknown; restored from __doc__
""" x.__rlshift__(y) <==> y<<x """
pass
def __rmod__(self, y): # real signature unknown; restored from __doc__
""" x.__rmod__(y) <==> y%x """
pass
def __rmul__(self, y): # real signature unknown; restored from __doc__
""" x.__rmul__(y) <==> y*x """
pass
def __ror__(self, y): # real signature unknown; restored from __doc__
""" x.__ror__(y) <==> y|x """
pass
def __rpow__(self, x, z=None): # real signature unknown; restored from __doc__
""" y.__rpow__(x[, z]) <==> pow(x, y[, z]) """
pass
def __rrshift__(self, y): # real signature unknown; restored from __doc__
""" x.__rrshift__(y) <==> y>>x """
pass
def __rshift__(self, y): # real signature unknown; restored from __doc__
""" x.__rshift__(y) <==> x>>y """
pass
def __rsub__(self, y): # real signature unknown; restored from __doc__
""" x.__rsub__(y) <==> y-x """
pass
def __rtruediv__(self, y): # real signature unknown; restored from __doc__
""" x.__rtruediv__(y) <==> y/x """
pass
def __rxor__(self, y): # real signature unknown; restored from __doc__
""" x.__rxor__(y) <==> y^x """
pass
def __sizeof__(self, *args, **kwargs): # real signature unknown
""" Returns size in memory, in bytes """
pass
def __str__(self): # real signature unknown; restored from __doc__
""" x.__str__() <==> str(x) """
pass
def __sub__(self, y): # real signature unknown; restored from __doc__
""" x.__sub__(y) <==> x-y """
pass
def __truediv__(self, y): # real signature unknown; restored from __doc__
""" x.__truediv__(y) <==> x/y """
pass
def __trunc__(self, *args, **kwargs): # real signature unknown
""" Truncating an Integral returns itself. """
pass
def __xor__(self, y): # real signature unknown; restored from __doc__
""" x.__xor__(y) <==> x^y """
pass
denominator = property(lambda self: object(), lambda self, v: None, lambda self: None) # default
"""the denominator of a rational number in lowest terms"""
imag = property(lambda self: object(), lambda self, v: None, lambda self: None) # default
"""the imaginary part of a complex number"""
numerator = property(lambda self: object(), lambda self, v: None, lambda self: None) # default
"""the numerator of a rational number in lowest terms"""
real = property(lambda self: object(), lambda self, v: None, lambda self: None) # default
"""the real part of a complex number"""
long
long
注：跟C语言不同，Python的长整数没有指定位宽，即：Python没有限制长整数数值的大小，但实际上由于机器内存有限，我们使用的长整数数值不可能无限大。自从Python2.2起，如果整数发生溢出，Python会自动将整数数据转换为长整数，所以如今在长整数数据后面不加字母L也不会导致严重后果
三、浮点型
如：3.14、2.88
类型常用功能：
1 #浮点型功能与整形基本类似
更多功能：
class float(object):
"""
float(x) -> floating point number
Convert a string or number to a floating point number, if possible.
"""
def as_integer_ratio(self):
""" 获取改值的最简比 """
"""
float.as_integer_ratio() -> (int, int)
Return a pair of integers, whose ratio is exactly equal to the original
float and with a positive denominator.
Raise OverflowError on infinities and a ValueError on NaNs.
>>> (10.0).as_integer_ratio()
(10, 1)
>>> (0.0).as_integer_ratio()
(0, 1)
>>> (-.25).as_integer_ratio()
(-1, 4)
"""
pass
def conjugate(self, *args, **kwargs): # real signature unknown
""" Return self, the complex conjugate of any float. """
pass
def fromhex(self, string):
""" 将十六进制字符串转换成浮点型 """
"""
float.fromhex(string) -> float
Create a floating-point number from a hexadecimal string.
>>> float.fromhex('0x1.ffffp10')
2047.984375
>>> float.fromhex('-0x1p-1074')
-4.9406564584124654e-324
"""
return 0.0
def hex(self):
""" 返回当前值的 16 进制表示 """
"""
float.hex() -> string
Return a hexadecimal representation of a floating-point number.
>>> (-0.1).hex()
'-0x1.999999999999ap-4'
>>> 3.14159.hex()
'0x1.921f9f01b866ep+1'
"""
return ""
def is_integer(self, *args, **kwargs): # real signature unknown
""" Return True if the float is an integer. """
pass
def __abs__(self):
""" x.__abs__() <==> abs(x) """
pass
def __add__(self, y):
""" x.__add__(y) <==> x+y """
pass
def __coerce__(self, y):
""" x.__coerce__(y) <==> coerce(x, y) """
pass
def __divmod__(self, y):
""" x.__divmod__(y) <==> divmod(x, y) """
pass
def __div__(self, y):
""" x.__div__(y) <==> x/y """
pass
def __eq__(self, y):
""" x.__eq__(y) <==> x==y """
pass
def __float__(self):
""" x.__float__() <==> float(x) """
pass
def __floordiv__(self, y):
""" x.__floordiv__(y) <==> x//y """
pass
def __format__(self, format_spec):
"""
float.__format__(format_spec) -> string
Formats the float according to format_spec.
"""
return ""
def __getattribute__(self, name):
""" x.__getattribute__('name') <==> x.name """
pass
def __getformat__(self, typestr):
"""
float.__getformat__(typestr) -> string
You probably don't want to use this function. It exists mainly to be
used in Python's test suite.
typestr must be 'double' or 'float'. This function returns whichever of
'unknown', 'IEEE, big-endian' or 'IEEE, little-endian' best describes the
format of floating point numbers used by the C type named by typestr.
"""
return ""
def __getnewargs__(self, *args, **kwargs): # real signature unknown
pass
def __ge__(self, y):
""" x.__ge__(y) <==> x>=y """
pass
def __gt__(self, y):
""" x.__gt__(y) <==> x>y """
pass
def __hash__(self):
""" x.__hash__() <==> hash(x) """
pass
def __init__(self, x):
pass
def __int__(self):
""" x.__int__() <==> int(x) """
pass
def __le__(self, y):
""" x.__le__(y) <==> x<=y """
pass
def __long__(self):
""" x.__long__() <==> long(x) """
pass
def __lt__(self, y):
""" x.__lt__(y) <==> x<y """
pass
def __mod__(self, y):
""" x.__mod__(y) <==> x%y """
pass
def __mul__(self, y):
""" x.__mul__(y) <==> x*y """
pass
def __neg__(self):
""" x.__neg__() <==> -x """
pass
@staticmethod # known case of __new__
def __new__(S, *more):
""" T.__new__(S, ...) -> a new object with type S, a subtype of T """
pass
def __ne__(self, y):
""" x.__ne__(y) <==> x!=y """
pass
def __nonzero__(self):
""" x.__nonzero__() <==> x != 0 """
pass
def __pos__(self):
""" x.__pos__() <==> +x """
pass
def __pow__(self, y, z=None):
""" x.__pow__(y[, z]) <==> pow(x, y[, z]) """
pass
def __radd__(self, y):
""" x.__radd__(y) <==> y+x """
pass
def __rdivmod__(self, y):
""" x.__rdivmod__(y) <==> divmod(y, x) """
pass
def __rdiv__(self, y):
""" x.__rdiv__(y) <==> y/x """
pass
def __repr__(self):
""" x.__repr__() <==> repr(x) """
pass
def __rfloordiv__(self, y):
""" x.__rfloordiv__(y) <==> y//x """
pass
def __rmod__(self, y):
""" x.__rmod__(y) <==> y%x """
pass
def __rmul__(self, y):
""" x.__rmul__(y) <==> y*x """
pass
def __rpow__(self, x, z=None):
""" y.__rpow__(x[, z]) <==> pow(x, y[, z]) """
pass
def __rsub__(self, y):
""" x.__rsub__(y) <==> y-x """
pass
def __rtruediv__(self, y):
""" x.__rtruediv__(y) <==> y/x """
pass
def __setformat__(self, typestr, fmt):
"""
float.__setformat__(typestr, fmt) -> None
You probably don't want to use this function. It exists mainly to be
used in Python's test suite.
typestr must be 'double' or 'float'. fmt must be one of 'unknown',
'IEEE, big-endian' or 'IEEE, little-endian', and in addition can only be
one of the latter two if it appears to match the underlying C reality.
Override the automatic determination of C-level floating point type.
This affects how floats are converted to and from binary strings.
"""
pass
def __str__(self):
""" x.__str__() <==> str(x) """
pass
def __sub__(self, y):
""" x.__sub__(y) <==> x-y """
pass
def __truediv__(self, y):
""" x.__truediv__(y) <==> x/y """
pass
def __trunc__(self, *args, **kwargs): # real signature unknown
""" Return the Integral closest to x between 0 and x. """
pass
imag = property(lambda self: object(), lambda self, v: None, lambda self: None) # default
"""the imaginary part of a complex number"""
real = property(lambda self: object(), lambda self, v: None, lambda self: None) # default
"""the real part of a complex number"""
float
float
四、字符串
如：'wupeiqi'、'alex'、'solo'
类型常用功能：
name = "my name is solo"
print(name.capitalize()) #首字母大写
#My name is solo
print(name.count("l")) #统计字符串出现某个字符的个数
#2
print(name.center(30,"-")) #打印30个字符，不够的-补齐
#--------my name is solo--------
print(name.ljust(30,"-")) #打印30个字符，不够的-补齐，字符串在左边
#my name is solo----------------
print(name.endswith("solo")) #判断字符串是否以solo结尾
#True
print(name[name.find("na"):]) #find寻找na所在的索引下标 字符串也可以切片
#name is solo
print("5.3".isdigit()) #判断字符是否为整数
#False
print("a_1A".isidentifier()) #判断是不是一个合法的标识符（变量名）
#True
print("+".join(["1","2","3"])) #把join后的内容加入到前面字符串中，以+为分割符
#1+2+3
print("\nsolo".strip()) #去换行符
#solo
print("1+2+3+4".split("+")) #以+为分隔符生成新的列表，默认不写为空格
#['1', '2', '3', '4']
name = "my name is {name} and i an {year} old"
print(name.format(name="solo",year=20)
#my name is solo and i an 20 old
print(name.format_map({"name":"solo","year":20})) #很少用
#my name is solo and i an 20 old
p = str.maketrans("abcdefli","12345678") #转换 一一对应
print("lianzhilei".translate(p))
#781nzh8758
更多功能：
class str(basestring):
"""
str(object='') -> string
Return a nice string representation of the object.
If the argument is a string, the return value is the same object.
"""
def capitalize(self):
""" 首字母变大写 """
"""
S.capitalize() -> string
Return a copy of the string S with only its first character
capitalized.
"""
return ""
def center(self, width, fillchar=None):
""" 内容居中，width：总长度；fillchar：空白处填充内容，默认无 """
"""
S.center(width[, fillchar]) -> string
Return S centered in a string of length width. Padding is
done using the specified fill character (default is a space)
"""
return ""
def count(self, sub, start=None, end=None):
""" 子序列个数 """
"""
S.count(sub[, start[, end]]) -> int
Return the number of non-overlapping occurrences of substring sub in
string S[start:end]. Optional arguments start and end are interpreted
as in slice notation.
"""
return 0
def decode(self, encoding=None, errors=None):
""" 解码 """
"""
S.decode([encoding[,errors]]) -> object
Decodes S using the codec registered for encoding. encoding defaults
to the default encoding. errors may be given to set a different error
handling scheme. Default is 'strict' meaning that encoding errors raise
a UnicodeDecodeError. Other possible values are 'ignore' and 'replace'
as well as any other name registered with codecs.register_error that is
able to handle UnicodeDecodeErrors.
"""
return object()
def encode(self, encoding=None, errors=None):
""" 编码，针对unicode """
"""
S.encode([encoding[,errors]]) -> object
Encodes S using the codec registered for encoding. encoding defaults
to the default encoding. errors may be given to set a different error
handling scheme. Default is 'strict' meaning that encoding errors raise
a UnicodeEncodeError. Other possible values are 'ignore', 'replace' and
'xmlcharrefreplace' as well as any other name registered with
codecs.register_error that is able to handle UnicodeEncodeErrors.
"""
return object()
def endswith(self, suffix, start=None, end=None):
""" 是否以 xxx 结束 """
"""
S.endswith(suffix[, start[, end]]) -> bool
Return True if S ends with the specified suffix, False otherwise.
With optional start, test S beginning at that position.
With optional end, stop comparing S at that position.
suffix can also be a tuple of strings to try.
"""
return False
def expandtabs(self, tabsize=None):
""" 将tab转换成空格，默认一个tab转换成8个空格 """
"""
S.expandtabs([tabsize]) -> string
Return a copy of S where all tab characters are expanded using spaces.
If tabsize is not given, a tab size of 8 characters is assumed.
"""
return ""
def find(self, sub, start=None, end=None):
""" 寻找子序列位置，如果没找到，返回 -1 """
"""
S.find(sub [,start [,end]]) -> int
Return the lowest index in S where substring sub is found,
such that sub is contained within S[start:end]. Optional
arguments start and end are interpreted as in slice notation.
Return -1 on failure.
"""
return 0
def format(*args, **kwargs): # known special case of str.format
""" 字符串格式化，动态参数，将函数式编程时细说 """
"""
S.format(*args, **kwargs) -> string
Return a formatted version of S, using substitutions from args and kwargs.
The substitutions are identified by braces ('{' and '}').
"""
pass
def index(self, sub, start=None, end=None):
""" 子序列位置，如果没找到，报错 """
S.index(sub [,start [,end]]) -> int
Like S.find() but raise ValueError when the substring is not found.
"""
return 0
def isalnum(self):
""" 是否是字母和数字 """
"""
S.isalnum() -> bool
Return True if all characters in S are alphanumeric
and there is at least one character in S, False otherwise.
"""
return False
def isalpha(self):
""" 是否是字母 """
"""
S.isalpha() -> bool
Return True if all characters in S are alphabetic
and there is at least one character in S, False otherwise.
"""
return False
def isdigit(self):
""" 是否是数字 """
"""
S.isdigit() -> bool
Return True if all characters in S are digits
and there is at least one character in S, False otherwise.
"""
return False
def islower(self):
""" 是否小写 """
"""
S.islower() -> bool
Return True if all cased characters in S are lowercase and there is
at least one cased character in S, False otherwise.
"""
return False
def isspace(self):
"""
S.isspace() -> bool
Return True if all characters in S are whitespace
and there is at least one character in S, False otherwise.
"""
return False
def istitle(self):
"""
S.istitle() -> bool
Return True if S is a titlecased string and there is at least one
character in S, i.e. uppercase characters may only follow uncased
characters and lowercase characters only cased ones. Return False
otherwise.
"""
return False
def isupper(self):
"""
S.isupper() -> bool
Return True if all cased characters in S are uppercase and there is
at least one cased character in S, False otherwise.
"""
return False
def join(self, iterable):
""" 连接 """
"""
S.join(iterable) -> string
Return a string which is the concatenation of the strings in the
iterable. The separator between elements is S.
"""
return ""
def ljust(self, width, fillchar=None):
""" 内容左对齐，右侧填充 """
"""
S.ljust(width[, fillchar]) -> string
Return S left-justified in a string of length width. Padding is
done using the specified fill character (default is a space).
"""
return ""
def lower(self):
""" 变小写 """
"""
S.lower() -> string
Return a copy of the string S converted to lowercase.
"""
return ""
def lstrip(self, chars=None):
""" 移除左侧空白 """
"""
S.lstrip([chars]) -> string or unicode
Return a copy of the string S with leading whitespace removed.
If chars is given and not None, remove characters in chars instead.
If chars is unicode, S will be converted to unicode before stripping
"""
return ""
def partition(self, sep):
""" 分割，前，中，后三部分 """
"""
S.partition(sep) -> (head, sep, tail)
Search for the separator sep in S, and return the part before it,
the separator itself, and the part after it. If the separator is not
found, return S and two empty strings.
"""
pass
def replace(self, old, new, count=None):
""" 替换 """
"""
S.replace(old, new[, count]) -> string
Return a copy of string S with all occurrences of substring
old replaced by new. If the optional argument count is
given, only the first count occurrences are replaced.
"""
return ""
def rfind(self, sub, start=None, end=None):
"""
S.rfind(sub [,start [,end]]) -> int
Return the highest index in S where substring sub is found,
such that sub is contained within S[start:end]. Optional
arguments start and end are interpreted as in slice notation.
Return -1 on failure.
"""
return 0
def rindex(self, sub, start=None, end=None):
"""
S.rindex(sub [,start [,end]]) -> int
Like S.rfind() but raise ValueError when the substring is not found.
"""
return 0
def rjust(self, width, fillchar=None):
"""
S.rjust(width[, fillchar]) -> string
Return S right-justified in a string of length width. Padding is
done using the specified fill character (default is a space)
"""
return ""
def rpartition(self, sep):
"""
S.rpartition(sep) -> (head, sep, tail)
Search for the separator sep in S, starting at the end of S, and return
the part before it, the separator itself, and the part after it. If the
separator is not found, return two empty strings and S.
"""
pass
def rsplit(self, sep=None, maxsplit=None):
"""
S.rsplit([sep [,maxsplit]]) -> list of strings
Return a list of the words in the string S, using sep as the
delimiter string, starting at the end of the string and working
to the front. If maxsplit is given, at most maxsplit splits are
done. If sep is not specified or is None, any whitespace string
is a separator.
"""
return []
def rstrip(self, chars=None):
"""
S.rstrip([chars]) -> string or unicode
Return a copy of the string S with trailing whitespace removed.
If chars is given and not None, remove characters in chars instead.
If chars is unicode, S will be converted to unicode before stripping
"""
return ""
def split(self, sep=None, maxsplit=None):
""" 分割， maxsplit最多分割几次 """
"""
S.split([sep [,maxsplit]]) -> list of strings
Return a list of the words in the string S, using sep as the
delimiter string. If maxsplit is given, at most maxsplit
splits are done. If sep is not specified or is None, any
whitespace string is a separator and empty strings are removed
from the result.
"""
return []
def splitlines(self, keepends=False):
""" 根据换行分割 """
"""
S.splitlines(keepends=False) -> list of strings
Return a list of the lines in S, breaking at line boundaries.
Line breaks are not included in the resulting list unless keepends
is given and true.
"""
return []
def startswith(self, prefix, start=None, end=None):
""" 是否起始 """
"""
S.startswith(prefix[, start[, end]]) -> bool
Return True if S starts with the specified prefix, False otherwise.
With optional start, test S beginning at that position.
With optional end, stop comparing S at that position.
prefix can also be a tuple of strings to try.
"""
return False
def strip(self, chars=None):
""" 移除两段空白 """
"""
S.strip([chars]) -> string or unicode
Return a copy of the string S with leading and trailing
whitespace removed.
If chars is given and not None, remove characters in chars instead.
If chars is unicode, S will be converted to unicode before stripping
"""
return ""
def swapcase(self):
""" 大写变小写，小写变大写 """
"""
S.swapcase() -> string
Return a copy of the string S with uppercase characters
converted to lowercase and vice versa.
"""
return ""
def title(self):
"""
S.title() -> string
Return a titlecased version of S, i.e. words start with uppercase
characters, all remaining cased characters have lowercase.
"""
return ""
def translate(self, table, deletechars=None):
"""
转换，需要先做一个对应表，最后一个表示删除字符集合
intab = "aeiou"
outtab = "12345"
trantab = maketrans(intab, outtab)
str = "this is string example....wow!!!"
print str.translate(trantab, 'xm')
"""
"""
S.translate(table [,deletechars]) -> string
Return a copy of the string S, where all characters occurring
in the optional argument deletechars are removed, and the
remaining characters have been mapped through the given
translation table, which must be a string of length 256 or None.
If the table argument is None, no translation is applied and
the operation simply removes the characters in deletechars.
"""
return ""
def upper(self):
"""
S.upper() -> string
Return a copy of the string S converted to uppercase.
"""
return ""
def zfill(self, width):
"""方法返回指定长度的字符串，原字符串右对齐，前面填充0。"""
"""
S.zfill(width) -> string
Pad a numeric string S with zeros on the left, to fill a field
of the specified width. The string S is never truncated.
"""
return ""
def _formatter_field_name_split(self, *args, **kwargs): # real signature unknown
pass
def _formatter_parser(self, *args, **kwargs): # real signature unknown
pass
def __add__(self, y):
""" x.__add__(y) <==> x+y """
pass
def __contains__(self, y):
""" x.__contains__(y) <==> y in x """
pass
def __eq__(self, y):
""" x.__eq__(y) <==> x==y """
pass
def __format__(self, format_spec):
"""
S.__format__(format_spec) -> string
Return a formatted version of S as described by format_spec.
"""
return ""
def __getattribute__(self, name):
""" x.__getattribute__('name') <==> x.name """
pass
def __getitem__(self, y):
""" x.__getitem__(y) <==> x[y] """
pass
def __getnewargs__(self, *args, **kwargs): # real signature unknown
pass
def __getslice__(self, i, j):
"""
x.__getslice__(i, j) <==> x[i:j]
Use of negative indices is not supported.
"""
pass
def __ge__(self, y):
""" x.__ge__(y) <==> x>=y """
pass
def __gt__(self, y):
""" x.__gt__(y) <==> x>y """
pass
def __hash__(self):
""" x.__hash__() <==> hash(x) """
pass
def __init__(self, string=''): # known special case of str.__init__
"""
str(object='') -> string
Return a nice string representation of the object.
If the argument is a string, the return value is the same object.
# (copied from class doc)
"""
pass
def __len__(self):
""" x.__len__() <==> len(x) """
pass
def __le__(self, y):
""" x.__le__(y) <==> x<=y """
pass
def __lt__(self, y):
""" x.__lt__(y) <==> x<y """
pass
def __mod__(self, y):
""" x.__mod__(y) <==> x%y """
pass
def __mul__(self, n):
""" x.__mul__(n) <==> x*n """
pass
@staticmethod # known case of __new__
def __new__(S, *more):
""" T.__new__(S, ...) -> a new object with type S, a subtype of T """
pass
def __ne__(self, y):
""" x.__ne__(y) <==> x!=y """
pass
def __repr__(self):
""" x.__repr__() <==> repr(x) """
pass
def __rmod__(self, y):
""" x.__rmod__(y) <==> y%x """
pass
def __rmul__(self, n):
""" x.__rmul__(n) <==> n*x """
pass
def __sizeof__(self):
""" S.__sizeof__() -> size of S in memory, in bytes """
pass
def __str__(self):
""" x.__str__() <==> str(x) """
pass
str
str
五、列表
如：[11,22,33,44,55]、['wupeiqi', 'alex','solo']
1、创建列表：
1 #两种创建方式 2 name_list = ['alex', 'seven', 'eric'] 3 name_list = list(['alex', 'seven', 'eric'])
2、列表类常用功能：
① 切片
name_list = ["Alex","Tenglan","Eric","Rain","Tom","Amy"] print(name_list[0:3]) #取下标0至下标3之间的元素，包括0，不包括3 #['Alex', 'Tenglan', 'Eric'] print(name_list[:3]) #:前什么都不写，表示从0开始，效果跟上句一样 #['Alex', 'Tenglan', 'Eric'] print(name_list[3:]) #:后什么不写，表示取值到最后 #['Rain', 'Tom', 'Amy'] print(name_list[:]) #:前后都不写，表示取值所有 #['Alex', 'Tenglan', 'Eric', 'Rain', 'Tom', 'Amy'] print(name_list[-3:-1]) #从-3开始到-1，包括-3，不包括-1 #['Rain', 'Tom'] print(name_list[1:-1]) #从1开始到-1，下标有正有负时，正数在前负数在后 #['Tenglan', 'Eric', 'Rain', 'Tom'] print(name_list[::2]) #2表示，每个1个元素，就取一个 #['Alex', 'Eric', 'Tom'] #注：[-1:0] [0:0] [-1:2] 都是空
② 追加
1 name_list = ["Alex","Tenglan","Eric","Rain","Tom","Amy"]
2 name_list.append("new") #append追加，加到最后，只能添加一个
3 print(name_list)
4 #['Alex', 'Tenglan', 'Eric', 'Rain', 'Tom', 'Amy', 'new']
③ 插入
1 name_list = ["Alex","Tenglan","Eric","Rain","Tom","Amy"] 2 name_list.insert(3,"new") #insert插入,把"new"加到下标3的位置 3 print(name_list)
④ 修改
1 name_list = ["Alex","Tenglan","Eric","Rain","Tom","Amy"] 2 name_list[2] = "solo" #把下标2的字符串换成solo 3 print(name_list)
⑤ 删除
#3种删除方式
name_list = ["Alex","Tenglan","Eric","Rain","Tom","Amy"]
del name_list[3] #del删除，指定要删除的下标
print(name_list)
#['Alex', 'Tenglan', 'Eric', 'Tom', 'Amy']
name_list.remove("Tenglan") #remove删除，指定要删除的字符
print(name_list)
#['Alex', 'Eric', 'Tom', 'Amy']
name_list.pop() #pop删除，删除列表最后一个值
print(name_list)
#['Alex', 'Eric', 'Tom']
⑥ 扩展
1 name_list = ["Alex","Tenglan","Eric","Rain","Tom","Amy"] 2 age_list = [11,22,33] 3 name_list.extend(age_list) #extend扩展,把列表age_list添加到name_list列表 4 print(name_list)
⑦ 拷贝
1 name_list = ["Alex","Tenglan","Eric","Rain","Tom","Amy"] 2 copy_list = name_list.copy() #copy拷贝，对列表进行复制 3 print(copy_list) 4 #注：之后会整理深浅copy的详细区分
⑧ 统计
1 name_list = ["Alex","Tenglan","Eric","Amy","Tom","Amy"]
2 print(name_list.count("Amy")) #count统计,统计列表Amy的个数
⑨ 排序和翻转
1 name_list = ["Alex","Tenglan","Eric","Rain","Tom","Amy","1","2","3"] 2 name_list.sort() #sort排序，对列表进行排序 3 print(name_list) 4 #['1', '2', '3', 'Alex', 'Amy', 'Eric', 'Rain', 'Tenglan', 'Tom'] 5 name_list.reverse() #reverse翻转，对列表进行翻转 6 print(name_list) 7 #['Tom', 'Tenglan', 'Rain', 'Eric', 'Amy', 'Alex', '3', '2', '1']
⑩ 获取下标
1 name_list = ["Alex","Tenglan","Eric","Rain","Tom","Amy"]
2 print(name_list.index("Tenglan")) #index索引,获取字符的下标
六、元组
如：(11,22,33,44,55)、('wupeiqi', 'alex','lzl')
1、创建元组：
#5种创建方式
age = 11,22,33,44,55 #直接写数字或者字符串，默认创建类型元组 字符串类型用引号'solo'
#输出： (11, 22, 33, 44, 55)
age = (11,22,33,44,55) #常见命名方式,()指定类型元组
#输出： (11, 22, 33, 44, 55)
age = tuple((11,22,33,44,55)) #tuple 以类的方式创建(()) 双括号 里面的()不可去掉
#输出： (11, 22, 33, 44, 55)
age = tuple([11,22,33,44,55]) #同(()) 效果一样 很少用 忘记它
#输出： (11, 22, 33, 44, 55)
age = tuple({11,22,33,44,55}) #({})创建的元组，随机排列 没卵用
#输出： (33, 11, 44, 22, 55)
2、元组类常用功能：
##count #统计元组字符出现的次数
name = ('wupeiqi', 'alex','solo')
print(name.count('alex'))
# 1
##index #查看字符串所在的索引位置
name = ('wupeiqi', 'alex','solo')
print(name.index('solo'))
# solo
七、字典 无序
如：{'name': 'wupeiqi', 'age': 18} 、{'host': 'solo.solo.solo.solo', 'port': 80}
注：字典一种key：value 的数据类型，也称键值对。字典dict是无序的，key值必须是唯一的，不能有重复。循环时，默认循环的是key
1、创建字典
#两种创建方式：
info_dic = {'stu1101': "TengLan Wu",'stu1102': "LongZe Luola",'stu1103': "XiaoZe Maliya",}
print(info_dic)
#{'stu1102': 'LongZe Luola', 'stu1101': 'TengLan Wu', 'stu1103': 'XiaoZe Maliya'}
info_dic = dict({'stu1101': "TengLan Wu",'stu1102': "LongZe Luola",'stu1103': "XiaoZe Maliya",})
print(info_dic)
#{'stu1102': 'LongZe Luola', 'stu1101': 'TengLan Wu', 'stu1103': 'XiaoZe Maliya'}
2、字典类常用功能：
① 增加
1 info_dic = {'stu1101': "TengLan Wu",'stu1102': "LongZe Luola",'stu1103': "XiaoZe Maliya",}
2 info_dic['stu1104'] = "JingKong Cang" #增加
3 print(info_dic)
② 修改
1 info_dic = {'stu1101': "TengLan Wu",'stu1102': "LongZe Luola",'stu1103': "XiaoZe Maliya",}
2 info_dic["stu1101"] = "Jingkong Cang" #有相应的key时为修改，没有为增加
3 print(info_dic)
③ 删除
#3种删除方式
info_dic = {'stu1101': "TengLan Wu",'stu1102': "LongZe Luola",'stu1103': "XiaoZe Maliya",}
info_dic.pop('stu1101') #pop删除,指定删除的key
print(info_dic)
#{'stu1103': 'XiaoZe Maliya', 'stu1102': 'LongZe Luola'}
del info_dic['stu1102'] #del删除，指定删除的key
print(info_dic)
#{'stu1103': 'XiaoZe Maliya'}
info_dic = {'stu1101': "TengLan Wu",'stu1102': "LongZe Luola",'stu1103': "XiaoZe Maliya",}
info_dic.popitem() #随机删除，没卵用
print(info_dic)
#{'stu1101': 'TengLan Wu', 'stu1103': 'XiaoZe Maliya'}
④ 查找value值
1 info_dic = {'stu1101': "TengLan Wu",'stu1102': "LongZe Luola",'stu1103': "XiaoZe Maliya",}
2 print(info_dic.get('stu1102')) #get查找，通过key查找value值
3 #LongZe Luola
4 print(info_dic['stu1102']) #通过key直接查找，但是如果输入查找的key不存在的话，就会报错，get则不会
5 #LongZe Luola
⑤ 字典多级嵌套
av_catalog = {
"欧美":{
"www.youporn.com": ["很多免费的,世界最大的","质量一般"],
"www.pornhub.com": ["很多免费的,也很大","质量比yourporn高点"],
"letmedothistoyou.com": ["多是自拍,高质量图片很多","资源不多,更新慢"],
"x-art.com":["质量很高,真的很高","全部收费,屌比请绕过"]
},
"日韩":{
"tokyo-hot":["质量怎样不清楚,个人已经不喜欢日韩范了","听说是收费的"]
},
"大陆":{
"1024":["全部免费,真好,好人一生平安","服务器在国外,慢"]
}
}
av_catalog["大陆"]["1024"][1] += ",可以用爬虫爬下来"
print(av_catalog["大陆"]["1024"])
#['全部免费,真好,好人一生平安', '服务器在国外,慢,可以用爬虫爬下来']
⑥ 循环
info_dic = {'stu1101': "TengLan Wu",'stu1102': "LongZe Luola",'stu1103': "XiaoZe Maliya",}
for stu_nu in info_dic:
print(stu_nu,info_dic[stu_nu]) #循环默认提取的是key
#stu1103 XiaoZe Maliya
#stu1101 TengLan Wu
#stu1102 LongZe Luola
for k,v in info_dic.items(): #先把dict生成list，数据量大的时候费时，不建议使用
print(k,v)
#stu1103 XiaoZe Maliya
#stu1101 TengLan Wu
#stu1102 LongZe Luola
八、集合
如：{'solo', 33, 'alex', 22, 'eric', 'wupeiqi', 11}
注：集合是一个无序的，不重复的数据组合。去重性，把一个列表变成集合，就自动去重了。关系测试，测试两组数据之前的交集、差集、并集
1、创建集合
1 #标准创建方式
2 info_set = set(["alex","wupeiqi","eric","solo",11,22,33])
3 print(info_set,type(info_set))
4 #{33, 11, 'wupeiqi', 'solo', 'alex', 'eric', 22} <class 'set'>
2、集合类常用功能
① 添加
#添加的两种方式
set_1 = set(["alex","wupeiqi","eric","solo"])
set_1.add(11) #add只能添加一个元素
print(set_1)
#{'alex', 'solo', 'eric', 11, 'wupeiqi'}
set_1 = set(["alex","wupeiqi","eric","solo"])
set_1.update([11,22,33])
print(set_1) #update可以添加多个元素
#{33, 11, 'alex', 'wupeiqi', 'eric', 22, 'solo'}
② 删除
#删除的三种方式
set_1 = set(["alex","wupeiqi","eric","solo",11,22,33])
set_1.remove("alex") #remove 删除指定元素
print(set_1)
#{'eric', 33, 'solo', 11, 22, 'wupeiqi'}
set_1.pop() #pop 随机删除元素
print(set_1)
#{33, 'wupeiqi', 11, 22, 'solo'}
set_1.discard("solo") #discard 删除指定元素，与remove区别在于，如果元素不存在也不会报错
set_1.discard(55)
print(set_1)
#{33, 'wupeiqi', 11, 22}
3、集合关系测试
① 交集
1 set_1 = set(["alex","wupeiqi","eric","solo",11,22,33])
2 set_2 = set([11,22,33,44,55,66])
3 print(set_1.intersection(set_2)) #intersection 取两个set的交集 set_1和set_2可以互换位置
4 #{33, 11, 22}
② 并集
1 set_1 = set(["alex","wupeiqi","eric","solo",11,22,33])
2 set_2 = set([11,22,33,44,55,66])
3 print(set_1.union(set_2)) #union 取两个set集合的并集 set_1和set_2可以互换位置
4 #{33, 66, 11, 44, 'eric', 55, 'solo', 22, 'wupeiqi', 'alex'}
③ 差集
1 set_1 = set(["alex","wupeiqi","eric","solo",11,22,33])
2 set_2 = set([11,22,33,44,55,66])
3 print(set_1.difference(set_2)) #difference 取两个set集合的差集 set_1有但是set_2没有的集合
4 #{'solo', 'eric', 'wupeiqi', 'alex'}
④ 子集、父集
set_1 = set(["alex","wupeiqi","eric","solo",11,22,33]) set_2 = set([11,22,33,44,55,66]) set_3 = set([11,22,33]) print(set_1.issubset(set_2)) #issubset 子集 #False print(set_1.issuperset(set_3)) #issuperset 父集 #True
⑤ 对称差集
1 set_1 = set(["alex","wupeiqi","eric","solo",11,22,33])
2 set_2 = set([11,22,33,44,55,66])
3 print(set_1.symmetric_difference(set_2)) #symmetric_difference 对称差集=两个集合并集减去合集
4 #{66, 'solo', 'eric', 'alex', 55, 'wupeiqi', 44}
⑥ 运算符做关系测试
set_1 = set(["alex","wupeiqi","eric","solo",11,22,33]) set_2 = set([11,22,33,44,55,66]) set_union = set_1 | set_2 # 并集 set_intersection = set_1 & set_2 # 交集 set_difference = set_1 - set_2 # 差集 set_symmetric_difference = set_1 ^ set_2 # 对称差集
六、模块初识
Python有大量的模块，从而使得开发Python程序非常简洁。类库有包括三中：
① 、Python内部提供的模块
②、业内开源的模块
③、程序员自己开发的模块：Python脚本的名字不要与模块名相同
1、sys模块（系统内置）
① sys.argv 用来捕获执行python脚本时传入的参数
② sys.stdin 标准信息输入
③ sys.stdout 标准定向输出
④ sys.stdout.flush 强制刷新标准输出缓存
import time
import sys
for i in range(5):
print(i),
sys.stdout.flush()
time.sleep(1)
# 这样设计是为了打印一个数每秒五秒钟，但如果您运行它，因为它是现在（取决于您的默认系统缓冲），
# 你可能看不到任何输出 CodeGo.net，直到再一次全部，你会看到0 1 2 3 4打印到屏幕上。
# 这是输出被缓冲，除非你sys.stdout之后每print你不会看到从输出中取出sys.stdout.flush()网上看到的差别
2、os模块（与系统进行交互）
① os.dir、os.popen调用当前系统命令
3、platform模块（识别当前运行的系统）
七、运算符
1、算数运算：
2、比较运算：
3、赋值运算：
4、逻辑运算：
5、成员运算：
6、身份运算：
7、位运算：
8、运算符优先级：
八、深浅拷贝剖析
1、对象赋值（创建列表变量Alex，变量包含子列表，通过变量Alex给变量solo赋值，然后对变量Alex的元素进行修改，此时solo会有什么变化呢？）
import copy #import调用copy模块
Alex = ["Alex", 28, ["Python", "C#", "JavaScript"]]
solo = Alex #直接赋值
# 修改前打印
print(id(Alex))
print(Alex)
print([id(adr) for adr in Alex])
# 输出： 7316664
# ['Alex', 28, ['Python', 'C#', 'JavaScript']]
# [2775776, 1398430400, 7318024]
print(id(solo))
print(solo)
print([id(adr) for adr in solo])
# 输出： 7316664
# ['Alex', 28, ['Python', 'C#', 'JavaScript']]
# [2775776, 1398430400, 7318024]
# 对变量进行修改
Alex[0]='Mr.Wu'
Alex[2].append('CSS')
print(id(Alex))
print(Alex)
print([id(adr) for adr in Alex])
# 输出： 7316664
# ['Mr.Wu', 28, ['Python', 'C#', 'JavaScript', 'CSS']]
# [5170528, 1398430400, 7318024]
print(id(solo))
print(solo)
print([id(adr) for adr in solo])
# 输出： 7316664
# ['Mr.Wu', 28, ['Python', 'C#', 'JavaScript', 'CSS']]
# [5170528, 1398430400, 7318024]
初始条件： Alex = ["Alex", 28, ["Python", "C#", "JavaScript"]]
对象赋值： solo = Alex #直接赋值
对象赋值结果：solo = ["Alex", 28, ["Python", "C#", "JavaScript"]]
对象赋值时是进行对象引用（内存地址）的传递，被赋值的变量并没有开辟新内存，两个变量共用一个内存地址
修改对象赋值：solo = ['Mr.Wu', 28, ['Python', 'C#', 'JavaScript', 'CSS']]
str是不可变类型，所以当修改元素Alex为Mr.Wu时，内存地址发生改变；list是可变类型，元素['Python', 'C#', 'JavaScript', 'CSS']修改完后，内存地址没有改变
2、浅拷贝（创建列表变量Alex，变量包含子列表，通过copy模块的浅拷贝函数copy()对变量Alex进行拷贝，当对Alex进行操作时，此时solo会如何变化？）
import copy #import调用copy模块
Alex = ["Alex", 28, ["Python", "C#", "JavaScript"]]
solo = copy.copy(Alex) #通过copy模块里面的浅拷贝函数copy()
# 修改前打印
print(id(Alex))
print(Alex)
print([id(adr) for adr in Alex])
# 输出： 10462472
# ['Alex', 28, ['Python', 'C#', 'JavaScript']]
# [5462752, 1359960768, 10463232]
print(id(solo))
print(solo)
print([id(adr) for adr in solo])
# 输出： 10201848
# ['Alex', 28, ['Python', 'C#', 'JavaScript']]
# [5462752, 1359960768, 10463232]
# 对变量进行修改
Alex[0]='Mr.Wu'
Alex[2].append('CSS')
print(id(Alex))
print(Alex)
print([id(adr) for adr in Alex])
# 输出： 10462472
# ['Mr.Wu', 28, ['Python', 'C#', 'JavaScript', 'CSS']]
# [10151264, 1359960768, 10463232]
print(id(solo))
print(solo)
print([id(adr) for adr in solo])
# 输出： 10201848
# ['Alex', 28, ['Python', 'C#', 'JavaScript', 'CSS']]
# [5462752, 1359960768, 10463232]
初始条件： Alex = ["Alex", 28, ["Python", "C#", "JavaScript"]]
浅拷贝： solo = copy.copy(Alex) #通过copy模块里面的浅拷贝函数copy()
浅拷贝结果： solo = ["Alex", 28, ["Python", "C#", "JavaScript"]]
浅拷贝时变量solo新建了一块内存(10201848),此内存记录了list中元素的地址；对于list中的元素，浅拷贝会使用原始元素的引用（内存地址）
修改浅拷贝： solo = ['Mr.Wu', 28, ['Python', 'C#', 'JavaScript', 'CSS']]
str是不可变类型，所以当修改元素Alex为Mr.Wu时，内存地址发生改变；list是可变类型，元素['Python', 'C#', 'JavaScript', 'CSS']修改完后，内存地址没有改变
3、深拷贝（创建列表变量Alex，变量包含子列表，通过copy模块的深拷贝函数deepcopy()对变量Alex进行拷贝，当对Alex进行操作时，此时solo会如何变化？）
#!/usr/bin/env python
# -*- coding:utf-8 -*-
#-Author-Lian
# 深拷贝
import copy #import调用copy模块
Alex = ["Alex", 28, ["Python", "C#", "JavaScript"]]
solo = copy.deepcopy(Alex) #通过copy模块里面的深拷贝函数deepcopy()
# 修改前打印
print(id(Alex))
print(Alex)
print([id(adr) for adr in Alex])
# 输出： 6202712
# ['Alex', 28, ['Python', 'C#', 'JavaScript']]
# [4086496, 1363237568, 6203472]
print(id(solo))
print(solo)
print([id(adr) for adr in solo])
# 输出： 6203032
# ['Alex', 28, ['Python', 'C#', 'JavaScript']]
# [4086496, 1363237568, 6203512]
# 对变量进行修改
Alex[0]='Mr.Wu'
Alex[2].append('CSS')
print(id(Alex))
print(Alex)
print([id(adr) for adr in Alex])
# 输出： 6202712
# ['Mr.Wu', 28, ['Python', 'C#', 'JavaScript', 'CSS']]
# [5236064, 1363237568, 6203472]
print(id(solo))
print(solo)
print([id(adr) for adr in solo])
# 输出： 6203032
# ['Alex', 28, ['Python', 'C#', 'JavaScript']]
# [4086496, 1363237568, 6203512]
初始条件： Alex = ["Alex", 28, ["Python", "C#", "JavaScript"]]
深拷贝： solo = copy.deepcopy(Alex) #通过copy模块里面的深拷贝函数deepcopy()
深拷贝结果： solo = ["Alex", 28, ["Python", "C#", "JavaScript"]]
深拷贝时变量solo新建了一块内存(10201848),此内存记录了list中元素的地址；但是，对于list中第三个元素（['Python', 'C#', 'JavaScript']）重新生成了一个地址（6203512），此时两个变量的第三个元素的内存引用地址不同
修改深拷贝： solo = ['Mr.Wu', 28, ['Python', 'C#', 'JavaScript', 'CSS']]
str是不可变类型，所以当修改元素Alex为Mr.Wu时，内存地址发生改变；list是可变类型，元素['Python', 'C#', 'JavaScript', 'CSS']修改完后，内存地址没有改变，但是Alex和solo在第三个元素引用的本就不同
4、对于拷贝有一些特殊情况
（1）对于非容器类型（如数字、字符串、和其他'原子'类型的对象）没有拷贝这一说
（2）也就是说，对于这些类型，"obj is copy.copy(obj)" 、"obj is copy.deepcopy(obj)"
（3）如果元祖变量只包含原子类型对象，则不能深拷贝
①为什么要拷贝？
答：当进行修改时，想要保留原来的数据和修改后的数据
②数字字符串 和 集合 在修改时的差异？ （深浅拷贝不同的终极原因）
答：在修改数据时：
数字字符串：在内存中新建一份数据
集合：修改内存中的同一份数据
③对于集合，如何保留其修改前和修改后的数据？
答：在内存中拷贝一份
④对于集合，如何拷贝其n层元素同时拷贝？
答：深拷贝
九、文件操作
（1）打开文件： 文件句柄 = file('文件路径', '模式')
python中打开文件有两种方式，即：open(...) 和 file(...) ，本质上前者在内部会调用后者来进行文件操作，推荐使用 open。
1、打开文件的模式：
r， 只读模式【默认】
w，只写模式【不可读；不存在则创建；存在则删除内容；】
a， 追加模式【不可读；不存在则创建；存在则只追加内容；】
2、"+" 同时读写某个文件：
r+，可读写文件。【可读；可写；可追加】
w+，写读
a+，追加读
1 总结1：r+模式下，如果在.write()进行写入内容前，有print()输出，则要写的内容会从文件尾部开始写入，使用的是读、追加模式；如果在.write()进行写入内容前，是seek()移动光标，则要写的内容会从移动到的光标开始进行写入，会把原来的内容覆盖掉，而不是整体后移，这点要记住；如果在.write()进行写入内容前，既没有print()也没有seek()光标移动，这种情况之前想的的情况，就是r+读写模式能先写后读吗？r+模式下默认光标在文件的首部，此时会直接从文件开头进行写入，效果等同于seek(0)。关于最后一点，参考a+模式。 2 总结2：读写模式一定要先写后读吗？能不能先读后写？ 如果先读的话，由于用的是w+模式打开的文件，打开后会清空原文件内容，所有读取的到东西是空的。另W+模式后期用的很少，了解即可，包括a+追加读这种模式；另w+模式下，光标会跟随文件写入移到到文件末尾，不用seek移到光标的话，打印内容为空 3 注：w+模式下，关于.write()跟seek()和print()的关系与r+模式下是一样一样的。w+打开文件后先清空，然后追加写，如果.write()前有seek()的话会从光标位置覆盖写。 4 总结3：通过上面的程序可以得出，a+模式下光标位置为文件末尾，如果要print()的话要结合seek()进行使用；另外与r+、w+不同的是，.write()与seek()没有关系，只能写内容到文件末尾，一直都是追加模式！
3、"U"表示在读取时，可以将 \r \n \r\n自动转换成 \n （与 r 或 r+ 模式同使用）
rU
r+U
4、"b"表示处理二进制文件（如：FTP发送上传ISO镜像文件，linux可忽略，windows处理二进制文件时需标注）
rb 二进制读
wb 二进制写(ab也一样)
ab
（2）文件操作常用功能：
1、read()、readline()、readlines()的区别
print(info_file.read()) #read参数，读取文件所有内容
print(info_file.readline()) #readline，只读取文章中的一行内容
print(info_file.readlines()) #readlines，把文章内容以换行符分割，并生成list格式，数据量大的话不建议使用
2、seek、tell光标
data = info_file.read() #默认光标在起始位置，.read（）读取完后，光标停留到文件末尾
print(info_file.tell()) #tell 获取当前的光标位
info_file.seek(0) #seek 移动光标到文件首部
3、文件循环
for index,line in enumerate(info_file.readlines()): #先把文件内容以行为分割生成列表，数据量大不能用
for line in info_file: #建议使用方法，每读取一行，内存会把之前的空间清空，不会占用太多内存
4、flush 刷新
sys.stdout.flush() #flush 强制刷新缓存到内存的数据写入硬盘
5、truncate 截断
truncate跟光标位置无关，从文件首部开始截取字符；如果是truncate(0)会把文件清空
6、with 语句
为了避免打开文件后忘记关闭，可以通过管理上下文，即：
with open('log','r') as f:
...
如此方式，当with代码块执行完毕时，内部会自动关闭并释放文件资源。在Python 2.7 后，with又支持同时对多个文件的上下文进行管理，即：
with open('log1') as obj1, open('log2') as obj2:
pass
（3）文件修改方式：
1、把文件读取到内存当中，对内存进行修改，把修改后的内容写入到原文件(旧内容被清空)
2、如果在硬盘上直接写，会进行覆盖，硬盘上不能进行插入，原来的内容不会整体后移，而是直接覆盖掉
3、把文件读取到内存当中，对内存进行修改，把修改的内容另存为新的文件(旧文件保留)
① 另存方式
② r+模式
③ a+模式
十、函数
①格式
def 函数名(参数):
....
函数体
....
return 返回值
函数名()
③实参： func("solo") // 'solo' 叫做函数func的实际参数，简称：实参
④默认参数： def stu_register(name,age,course,country="CN") // 位置参数
⑤关键参数： stu_register(age=22,name='lzl',course="python") // 关键参数必须放在位置参数之后
形参：在定义函数时，括号内的参数成为形参
特点：形参就是变量名
# def foo(x,y): #x=1,y=2
# print(x)
# print(y)
实参：在调用函数时，括号内的参数成为实参
特点：实参就是变量值
# foo(1,2)
在调用阶段实参（变量值）才会绑定形参（变量名）
调用结束后，解除绑定
参数的分类
位置参数：按照从左到右的顺序依次定义的参数
位置形参：必须被传值，并且多一个不行，少一个也不行
位置实参：与形参按照位置一一对应
# def foo(x,y):
# print(x)
# print(y)
#
# foo('egon',1,2)
关键字实参：指的是按照name=value的形式，指名道姓地给name传值
# def foo(name,age):
# print(name)
# print(age)
# foo('egon',18)
# foo(age=18,name='egon')
关键字实参需要注意的问题是：
# def foo(name,age,sex):
# print(name)
# print(age)
# print(sex)
# foo('egon',18,'male')
# print('======>')
# foo(sex='male',age=18,name='egon')
# foo('egon',sex='male',age=18)
问题一:语法规定位置实参必须在关键字实参的前面
# foo('egon',sex='male',age=18)
问题二:一定不要对同一个形参传多次值
# foo('egon',sex='male',age=18,name='egon1')
# foo('male',age=18,name='egon1')
默认参数（默认形参）：在定义阶段，就已经为形参赋值，意味在调用阶段可以不用传值
# def foo(x,y=1111111):
# print(x)
# print(y)
#
#
# foo(1,'a')
#
# def register(name,age,sex='male'):
# print(name,age,sex)
#
#
# register('asb',73)
# register('wsb',38)
# register('ysb',84)
# register('yaya',28,'female')
默认参数需要注意的问题
问题一:默认参数必须放在位置参数之后
# def foo(y=1,x):
# print(x,y)
问题二：默认参数只在定义阶段赋值一次，而且仅一次
# x=100
# def foo(a,b=x):
# print(a,b)
#
# x=111111111111111111111111111111
# foo('egon'
问题三：默认参数的值应该定义成不可变类型
#可变长参数指的是实参的个数多了
#实参无非位置实参和关键字实参两种
#形参必须要两种机制来分别处理按照位置定义的实参溢出的情况：*
#跟按照关键字定义的实参溢出的情况：**
# def foo(x,y,*args): #nums=(3,4,5,6,7)
# print(x)
# print(y)
# print(args)
# foo(1,2,3,4,5,6,7) #*
# foo(1,2) #*
#*args的扩展用法
# def foo(x,y,*args): #*args=*(3,4,5,6,7)
# print(x)
# print(y)
# print(args)
#
# # foo(1,2,3,4,5,6,7) #*
#
#
# foo(1,2,*(3,4,5,6,7)) #foo(1,2,3,4,5,6,7)
# def foo(x,y=1,*args): #
# print(x)
# print(y)
# print(args)
#
# # foo('a','b',*(1,2,3,4,5,6,7)) #foo('a','b',1,2,3,4,5,6,7)
# # foo('egon',10,2,3,4,5,6,9,y=2) #报错
# foo('egon',10,2,3,4,5,6,9)
# def foo(x,y,**kwargs): #nums={'z':3,'b':2,'a':1}
# print(x)
# print(y)
# print(kwargs)
# foo(1,2,z=3,a=1,b=2) #**
# def foo(x,y,**kwargs): #kwargs={'z':3,'b':2,'a':1}
# print(x)
# print(y)
# print(kwargs)
#
# foo(1,2,**{'z':3,'b':2,'a':1}) #foo(1,2,a=1,z=3,b=2)
# def foo(x, y): #
# print(x)
# print(y)
#
# foo(**{'y':1,'x':2}) # foo(y=1,x=2)
# def foo(x,*args,**kwargs):#args=(2,3,4,5) kwargs={'b':1,'a':2}
# print(x)
# print(args)
# print(kwargs)
#
#
# foo(1,2,3,4,5,b=1,a=2)
#这俩东西*args，**kwargs干甚用？？？
def register(name,age,sex='male'):
print(name)
print(age)
print(sex)
# def wrapper(*args,**kwargs): #args=(1,2,3) kwargs={'a':1,'b':2}
# # print(args)
# # print(kwargs)
# register(*args,**kwargs)
# # register(*(1, 2, 3),**{'a': 1, 'b': 2})
# # register(1, 2, 3,a=1,b=2)
#
#
# wrapper(1,2,3,a=1,b=2)
import time
# def register(name,age,sex='male'):
# # start_time=time.time()
# print(name)
# print(age)
# print(sex)
# time.sleep(3)
# stop_time=time.time()
# print('run time is %s' %(stop_time-start_time))
# def wrapper(*args, **kwargs): #args=('egon',) kwargs={'age':18}
# start_time=time.time()
# register(*args, **kwargs)
# stop_time=time.time()
# print('run time is %s' %(stop_time-start_time))
#
#
# wrapper('egon',age=18)
# register('egon',18)
#命名关键字参数: 在*后面定义的形参称为命名关键字参数，必须是被以关键字实参的形式传值
# def foo(name,age,*args,sex='male',group):
# print(name)
# print(age)
# print(args)
# print(sex)
# print(group)
#
# foo('alex',18,19,20,300,group='group1')
def foo(name,age=18,*args,sex='male',group,**kwargs):
pass
参数另一种较好的讲解！
⑥动态参数/非固定参数（*args 和 **kwargs）：
1 （1）*args：*args会把多传入的实参变成一个元组的类型；即使传入的是list类型也会变成元组，成为元组中的一个元素；另函数中有*args与其他形参的时候，*args一定要写到其 他形参的后面，否则传入的实参都会被传入到*args当中打印成元组；还有如果没有多出传入的实参即*args没有值的时候，*args为空，不会报错。
2 （2）**kwargs：**kwargs会把多出的a=b这种类型的实参打印成字典的类型（要区分开与关键参数的区别，关键参数的实参有对应的形参），被当成多余的实参传入到了*args里面，所以**kwargs的值才为空，分别用*inf_list和**info_dict的方式传入到*args、**kwargs当中（stu_register("lzl",*info_list,**info_dict) //传入列表和字典）
3 总结：*args必须放到**kwargs前面（规定）；位置参数一定要放到关键参数之前（规定）；默认参数不能跟*args、**kwargs一块存在（会报错）。
⑦return 返回值： 如果不执行return，函数的默认返回值为None；当函数执行到return时，函数结束执行
⑧局部变量： name = "Alex Li" #定义变量name
1 def change_name(name): 2 name = "金角大王,一个有Tesla的男人" #函数内部更改变量 3 函数内部对变量进行更改后，生效范围仅限于函数内部，对外部变量没有影响，这种变量称为局部变量；函数内部也可以让变量全局生效，需要加参数global，这种情况很少用。
⑨递归函数： 如果一个函数在内部调用自身本身，这个函数就是递归函数
条件： 有结束条件、更深一层递归规模比上次递归有所减少、效率不高，递归层次过多会导致栈溢出
写一个递归：
def func(n1,n2): #获取斐波那契数列100之前的数字
if n1 > 100:
return
print(n1)
n3 = n1 + n2
func(n2,n3)
func(0,1)
⑩匿名函数：不需要显式的指定函数
1 #普通函数 #换成匿名函数 2 def calc(n): calc = lambda n:n**n 3 return n**n print(calc(10) 4 print(calc(10))
⑪高阶函数: 变量可以指向函数，函数的参数能接收变量，那么一个函数就可以接收另一个函数作为参数，这种函数就称之为高阶函数。
1 def add(x,y,f): 2 return f(x) + f(y) 3 res = add(3,-6,abs) 4 print(res)
⑫内置函数
⑬函数的调用顺序：被调用函数要在执行之前被定义
#函数错误的调用方式
def func(): #定义函数func()
print("in the func")
foo() #调用函数foo()
func() #执行函数func()
def foo(): #定义函数foo()
print("in the foo")
#函数正确的调用方式
def func(): #定义函数func()
print("in the func")
foo() #调用函数foo()
def foo(): #定义函数foo()
print("in the foo")
func() #执行函数func()
⑭高阶函数：1、某一函数当做参数传入另一个函数中。2、函数的返回值包含一个或多个函数
⑮内嵌函数：在一个函数体内创建另外一个函数（内嵌函数中定义的函数在全局中是无法直接执行的）
⑯装饰器：本质是函数（装饰其他函数），为其他函数添加附加功能的。
遵循原则: 1.不能修改被装饰函数的源代码 2.不能修改被装饰函数的调用方式
组成：装饰器由高阶函数+内嵌函数组成
⑰生成器：调用时才会生成相应数据的机制，称为生成器：generator
应用：可通过yield实现在单线程的情况下实现并发运算的效果(协程)
1 #!/usr/bin/env python
2 # -*- coding:utf-8 -*-
3 #-Author-solo
4 import time
5 def consumer(name):
6 print("%s 准备吃包子啦!" %name)
7 while True:
8 baozi = yield #yield的作用:保存当前状态并返回
9
10 print("包子[%s]来了,被[%s]吃了!" %(baozi,name))
11 def producer(name):
12 c = consumer('A')
13 c2 = consumer('B')
14 c.__next__() #c.__next__()等同于next(c)
15 c2.__next__() #next()作用：调用yield，不给yield传值
16 print("老子开始准备做包子啦!")
17 for i in range(10):
18 time.sleep(1)
19 print("%s做了2个包子!"%(name))
20 c.send(i) #send()作用：调用yield，给yield传值
21 c2.send(i)
22 producer("solo")
协程
⑱迭代器
可迭代对象：可以直接作用于for循环的对象：Iterable
可以直接作用于for循环的数据类型有：1、集合数据类型，如list、tuple、dict、set、str等；2、生成器，包括generator和带yield的generator function；
可以用isinstance()去判断一个对象是否是Iterable对象
|
1
2
3
|
from collections import Iterable
print(isinstance([], Iterable))
# True
|
迭代器：可以被next()函数调用并不断返回下一个值的对象称为迭代器：Iterator。
用isinstance()判断一个对象是否是Iterator对象
|
1
2
3
|
from collections import Iterator
print(isinstance([], Iterator))
# True
|
小结：
1、凡是可作用于for循环的对象都是Iterable类型；
2、凡是可作用于next()函数的对象都是Iterator类型，它们表示一个惰性计算的序列；
3、集合数据类型如list、dict、str等是Iterable但不是Iterator，不过可以通过iter()函数获得一个Iterator对象；
4、Python的for循环本质上就是通过不断调用next()函数实现的
1 for x in [1, 2, 3, 4, 5]: 2 pass
1 首先获得Iterator对象: 2 it = iter([1, 2, 3, 4, 5]) 3 # 循环: 4 while True: 5 try: 6 # 获得下一个值: 7 x = next(it) 8 except StopIteration: 9 # 遇到StopIteration就退出循环 10 break 等价效果（迭代器）
十一、常用模块
（一）、导入模块：导入模块的本质就是把python文件解释一遍；导入包的本质就是把包文件下面的init.py文件运行一遍
（二）、常用模块：
（1）time和datatime模块
时间相关的操作，时间有三种表示方式：1、时间戳 1970年1月1日之后的秒，即：time.time()
2、格式化的字符串 2014-11-11 11:11， 即：time.strftime('%Y-%m-%d')
3、结构化时间 元组包含了：年、日、星期等... time.struct_time 即：time.localtime()
1 import time
2 print(time.time()) #时间戳
3 #1472037866.0750718
4 print(time.localtime()) #结构化时间
5 #time.struct_time(tm_year=2016, tm_mon=8, tm_mday=25, tm_hour=8, tm_min=44, tm_sec=46, tm_wday=3, tm_yday=238, tm_isdst=0)
6 print(time.strftime('%Y-%m-%d')) #格式化的字符串
7 #2016-08-25
8 print(time.strftime('%Y-%m-%d',time.localtime()))
9 #2016-08-25
10 print(time.gmtime()) #结构化时间
11 #time.struct_time(tm_year=2016, tm_mon=8, tm_mday=25, tm_hour=3, tm_min=8, tm_sec=48, tm_wday=3, tm_yday=238, tm_isdst=0)
12 print(time.strptime('2014-11-11', '%Y-%m-%d')) #结构化时间
13 #time.struct_time(tm_year=2014, tm_mon=11, tm_mday=11, tm_hour=0, tm_min=0, tm_sec=0, tm_wday=1, tm_yday=315, tm_isdst=-1)
14 print(time.asctime())
15 #Thu Aug 25 11:15:10 2016
16 print(time.asctime(time.localtime()))
17 #Thu Aug 25 11:15:10 2016
18 print(time.ctime(time.time()))
19 #Thu Aug 25 11:15:10 2016
time模块
1 import datetime 2 print(datetime.date) #表示日期的类。常用的属性有year, month, day 3 #<class 'datetime.date'> 4 print(datetime.time) #表示时间的类。常用的属性有hour, minute, second, microsecond 5 #<class 'datetime.time'> 6 print(datetime.datetime) #表示日期时间 7 #<class 'datetime.datetime'> 8 print(datetime.timedelta) #表示时间间隔，即两个时间点之间的长度 9 #<class 'datetime.timedelta'> 10 print(datetime.datetime.now()) 11 #2016-08-25 14:21:07.722285 12 print(datetime.datetime.now() - datetime.timedelta(days=5)) 13 #2016-08-20 14:21:28.275460 datetime模块
1 import time 2 3 str = '2017-03-26 3:12' 4 str2 = '2017-05-26 13:12' 5 date1 = time.strptime(str, '%Y-%m-%d %H:%M') 6 date2 = time.strptime(str2, '%Y-%m-%d %H:%M') 7 if float(time.time()) >= float(time.mktime(date1)) and float(time.time()) <= float(time.mktime(date2)): 8 print 'cccccccc' 9 10 11 import datetime 12 13 str = '2017-03-26 3:12' 14 str2 = '2017-05-26 13:12' 15 date1 = datetime.datetime.strptime(str,'%Y-%m-%d %H:%M') 16 date2 = datetime.datetime.strptime(str2,'%Y-%m-%d %H:%M') 17 datenow = datetime.datetime.now() 18 if datenow <date1: 19 print 'dddddd' 20 21 时间比较 时间比较
（2）random模块：生成随机数（验证码）
1 #random随机数模块
2 import random
3 print(random.random()) #生成0到1的随机数
4 #0.7308387398872364
5 print(random.randint(1,3)) #生成1-3随机数
6 #3
7 print(random.randrange(1,3)) #生成1-2随机数，不包含3
8 #2
9 print(random.choice("hello")) #随机选取字符串
10 #e
11 print(random.sample("hello",2)) #随机选取特定的字符
12 #['l', 'h']
13 items = [1,2,3,4,5,6,7]
14 random.shuffle(items)
15 print(items)
16 #[2, 3, 1, 6, 4, 7, 5]
生成随机数
1 import random 2 checkcode = '' 3 for i in range(4): 4 current = random.randrange(0,4) 5 if current != i: 6 temp = chr(random.randint(65,90)) 7 else: 8 temp = random.randint(0,9) 9 checkcode += str(temp) 10 print(checkcode) 11 #51T6 验证码
（3）os模块：用于提供系统级别的操作（比如目录、路径等的操作）
1 import os
2 os.getcwd() #获取当前工作目录，即当前python脚本工作的目录路径
3 os.chdir("dirname") #改变当前脚本工作目录；相当于shell下cd
4 os.curdir #返回当前目录: ('.')
5 os.pardir #获取当前目录的父目录字符串名：('..')
6 os.makedirs('dirname1/dirname2') #可生成多层递归目录
7 os.removedirs('dirname1') # 若目录为空，则删除，并递归到上一级目录，如若也为空，则删除，依此类推
8 os.mkdir('dirname') # 生成单级目录；相当于shell中mkdir dirname
9 os.rmdir('dirname') #删除单级空目录，若目录不为空则无法删除，报错；相当于shell中rmdir dirname
10 os.listdir('dirname') #列出指定目录下的所有文件和子目录，包括隐藏文件，并以列表方式打印
11 os.remove() # 删除一个文件
12 os.rename("oldname","newname") # 重命名文件/目录
13 os.stat('path/filename') # 获取文件/目录信息
14 os.sep #输出操作系统特定的路径分隔符，win下为"\\",Linux下为"/"
15 os.linesep #输出当前平台使用的行终止符，win下为"\t\n",Linux下为"\n"
16 os.pathsep #输出用于分割文件路径的字符串
17 os.name #输出字符串指示当前使用平台。win->'nt'; Linux->'posix'
18 os.system("bash command") #运行shell命令，直接显示
19 os.environ #获取系统环境变量
20 os.path.abspath(path) #返回path规范化的绝对路径
21 os.path.split(path) #将path分割成目录和文件名二元组返回
22 os.path.dirname(path) # 返回path的目录。其实就是os.path.split(path)的第一个元素
23 os.path.basename(path) # 返回path最后的文件名。如何path以／或\结尾，那么就会返回空值。即os.path.split(path)的第二个元素
24 os.path.exists(path) #如果path存在，返回True；如果path不存在，返回False
25 os.path.isabs(path) #如果path是绝对路径，返回True
26 os.path.isfile(path) #如果path是一个存在的文件，返回True。否则返回False
27 os.path.isdir(path) #如果path是一个存在的目录，则返回True。否则返回False
28 os.path.join(path1[, path2[, ...]]) # 将多个路径组合后返回，第一个绝对路径之前的参数将被忽略
29 os.path.getatime(path) #返回path所指向的文件或者目录的最后存取时间
30 os.path.getmtime(path) #返回path所指向的文件或者目录的最后修改时间
os模块
（4）sys模块：用于提供对解释器相关的操作（比如退出程序、版本信息等）
1 import sys
2 sys.argv #命令行参数List，第一个元素是程序本身路径
3 sys.exit(n) #退出程序，正常退出时exit(0)
4 sys.version # 获取Python解释程序的版本信息
5 sys.maxint #最大的Int值
6 sys.path #返回模块的搜索路径，初始化时使用PYTHONPATH环境变量的值
7 sys.platform #返回操作系统平台名称
8 sys.stdout.write('please:')
9 val = sys.stdin.readline()[:-1]
sys模块
（5）shutil模块：高级的（文件、文件夹、压缩包）处理模块 （比如文件的拷贝、压缩等）
① shutil.copyfileobj 将文件内容拷贝到另一个文件中，可以部分内容
1 def copyfileobj(fsrc, fdst, length=16*1024): 2 """copy data from file-like object fsrc to file-like object fdst""" 3 while 1: 4 buf = fsrc.read(length) 5 if not buf: 6 break 7 fdst.write(buf) shutil.copyfileobj
1 import shutil
2 f1 = open("fsrc",encoding="utf-8")
3 f2 = open("fdst",encoding="utf-8")
4 shutil.copyfile(f1,f2)
5 #把文件f1里的内容拷贝到f2当中
② shutil.copyfile 文件拷贝
1 def copyfile(src, dst):
2 """Copy data from src to dst"""
3 if _samefile(src, dst):
4 raise Error("`%s` and `%s` are the same file" % (src, dst))
5 for fn in [src, dst]:
6 try:
7 st = os.stat(fn)
8 except OSError:
9 # File most likely does not exist
10 pass
11 else:
12 # XXX What about other special files? (sockets, devices...)
13 if stat.S_ISFIFO(st.st_mode):
14 raise SpecialFileError("`%s` is a named pipe" % fn)
15 with open(src, 'rb') as fsrc:
16 with open(dst, 'wb') as fdst:
17 copyfileobj(fsrc, fdst)
shutil.copyfile
1 import shutil
2 shutil.copyfile("f1","f2")
3 #把文件f1里的内容拷贝到f2当中
③ shutil.copymode(src, dst) 仅拷贝权限。内容、组、用户均不变
1 def copymode(src, dst): 2 """Copy mode bits from src to dst""" 3 if hasattr(os, 'chmod'): 4 st = os.stat(src) 5 mode = stat.S_IMODE(st.st_mode) 6 os.chmod(dst, mode) shutil.copymode
④ shutil.copystat(src, dst) 拷贝状态的信息，包括：mode bits, atime, mtime, flags
1 def copystat(src, dst): 2 """Copy all stat info (mode bits, atime, mtime, flags) from src to dst""" 3 st = os.stat(src) 4 mode = stat.S_IMODE(st.st_mode) 5 if hasattr(os, 'utime'): 6 os.utime(dst, (st.st_atime, st.st_mtime)) 7 if hasattr(os, 'chmod'): 8 os.chmod(dst, mode) 9 if hasattr(os, 'chflags') and hasattr(st, 'st_flags'): 10 try: 11 os.chflags(dst, st.st_flags) 12 except OSError, why: 13 for err in 'EOPNOTSUPP', 'ENOTSUP': 14 if hasattr(errno, err) and why.errno == getattr(errno, err): 15 break 16 else: 17 raise shutil.copystat
⑤ shutil.copy(src, dst) 拷贝文件和权限
1 def copy(src, dst):
2 """Copy data and mode bits ("cp src dst").
3
4 The destination may be a directory.
5
6 """
7 if os.path.isdir(dst):
8 dst = os.path.join(dst, os.path.basename(src))
9 copyfile(src, dst)
10 copymode(src, dst)
shutil.copy
⑥ shutil.copy2(src, dst) 拷贝文件和状态信息
1 def copy2(src, dst):
2 """Copy data and all stat info ("cp -p src dst").
3
4 The destination may be a directory.
5
6 """
7 if os.path.isdir(dst):
8 dst = os.path.join(dst, os.path.basename(src))
9 copyfile(src, dst)
10 copystat(src, dst)
shutil.copy2
⑦ shutil.copytree(src, dst, symlinks=False, ignore=None) 递归的去拷贝文件 拷贝多层目录
1 def ignore_patterns(*patterns): 2 """Function that can be used as copytree() ignore parameter. 3 4 Patterns is a sequence of glob-style patterns 5 that are used to exclude files""" 6 def _ignore_patterns(path, names): 7 ignored_names = [] 8 for pattern in patterns: 9 ignored_names.extend(fnmatch.filter(names, pattern)) 10 return set(ignored_names) 11 return _ignore_patterns 12 def copytree(src, dst, symlinks=False, ignore=None): 13 """Recursively copy a directory tree using copy2(). 14 15 The destination directory must not already exist. 16 If exception(s) occur, an Error is raised with a list of reasons. 17 18 If the optional symlinks flag is true, symbolic links in the 19 source tree result in symbolic links in the destination tree; if 20 it is false, the contents of the files pointed to by symbolic 21 links are copied. 22 23 The optional ignore argument is a callable. If given, it 24 is called with the `src` parameter, which is the directory 25 being visited by copytree(), and `names` which is the list of 26 `src` contents, as returned by os.listdir(): 27 28 callable(src, names) -> ignored_names 29 30 Since copytree() is called recursively, the callable will be 31 called once for each directory that is copied. It returns a 32 list of names relative to the `src` directory that should 33 not be copied. 34 35 XXX Consider this example code rather than the ultimate tool. 36 37 """ 38 names = os.listdir(src) 39 if ignore is not None: 40 ignored_names = ignore(src, names) 41 else: 42 ignored_names = set() 43 44 os.makedirs(dst) 45 errors = [] 46 for name in names: 47 if name in ignored_names: 48 continue 49 srcname = os.path.join(src, name) 50 dstname = os.path.join(dst, name) 51 try: 52 if symlinks and os.path.islink(srcname): 53 linkto = os.readlink(srcname) 54 os.symlink(linkto, dstname) 55 elif os.path.isdir(srcname): 56 copytree(srcname, dstname, symlinks, ignore) 57 else: 58 # Will raise a SpecialFileError for unsupported file types copy2(srcname, dstname) 59 # catch the Error from the recursive copytree so that we can 60 # continue with other files 61 except Error, err: 62 errors.extend(err.args[0]) 63 except EnvironmentError, why: 64 errors.append((srcname, dstname, str(why))) 65 try: 66 copystat(src, dst) 67 except OSError, why: 68 if WindowsError is not None and isinstance(why, WindowsError): 69 # Copying file access times may fail on Windows 70 pass 71 else: 72 errors.append((src, dst, str(why))) 73 if errors: 74 raise Error, errors shutil.copytree
⑧ shutil.rmtree(path[, ignore_errors[, onerror]]) 递归的去删除文件
1 def rmtree(path, ignore_errors=False, onerror=None):
2 """Recursively delete a directory tree.
3
4 If ignore_errors is set, errors are ignored; otherwise, if onerror
5 is set, it is called to handle the error with arguments (func,
6 path, exc_info) where func is os.listdir, os.remove, or os.rmdir;
7 path is the argument to that function that caused it to fail; and
8 exc_info is a tuple returned by sys.exc_info(). If ignore_errors
9 is false and onerror is None, an exception is raised.
10
11 """
12 if ignore_errors:
13 def onerror(*args):
14 pass
15 elif onerror is None:
16 def onerror(*args):
17 raise
18 try:
19 if os.path.islink(path):
20 # symlinks to directories are forbidden, see bug #1669
21 raise OSError("Cannot call rmtree on a symbolic link")
22 except OSError:
23 onerror(os.path.islink, path, sys.exc_info())
24 # can't continue even if onerror hook returns
25 return
26 names = []
27 try:
28 names = os.listdir(path)
29 except os.error, err:
30 onerror(os.listdir, path, sys.exc_info())
31 for name in names:
32 fullname = os.path.join(path, name)
33 try:
34 mode = os.lstat(fullname).st_mode
35 except os.error:
36 mode = 0
37 if stat.S_ISDIR(mode):
38 rmtree(fullname, ignore_errors, onerror)
39 else:
40 try:
41 os.remove(fullname)
42 except os.error, err:
43 onerror(os.remove, fullname, sys.exc_info())
44 try:
45 os.rmdir(path)
46 except os.error:
47 onerror(os.rmdir, path, sys.exc_info())
shutil.rmtree
⑨ shutil.move(src, dst) 递归的去移动文件
1 def move(src, dst): 2 """Recursively move a file or directory to another location. This is 3 similar to the Unix "mv" command. 4 5 If the destination is a directory or a symlink to a directory, the source 6 is moved inside the directory. The destination path must not already 7 exist. 8 9 If the destination already exists but is not a directory, it may be 10 overwritten depending on os.rename() semantics. 11 12 If the destination is on our current filesystem, then rename() is used. 13 Otherwise, src is copied to the destination and then removed. 14 A lot more could be done here... A look at a mv.c shows a lot of 15 the issues this implementation glosses over. 16 17 """ 18 real_dst = dst 19 if os.path.isdir(dst): 20 if _samefile(src, dst): 21 # We might be on a case insensitive filesystem, 22 # perform the rename anyway. os.rename(src, dst) 23 return 24 25 real_dst = os.path.join(dst, _basename(src)) 26 if os.path.exists(real_dst): 27 raise Error, "Destination path '%s' already exists" % real_dst 28 try: 29 os.rename(src, real_dst) 30 except OSError: 31 if os.path.isdir(src): 32 if _destinsrc(src, dst): 33 raise Error, "Cannot move a directory '%s' into itself '%s'." % (src, dst) 34 copytree(src, real_dst, symlinks=True) 35 rmtree(src) 36 else: 37 copy2(src, real_dst) 38 os.unlink(src) shutil.move
⑩ shutil.make_archive(base_name, format,...) 创建压缩包并返回文件路径，例如：zip、tar
base_name： 压缩包的文件名，也可以是压缩包的路径。只是文件名时，则保存至当前目录，否则保存至指定路径，
如：www =>保存至当前路径
如：/Users/wupeiqi/www =>保存至/Users/wupeiqi/
format： 压缩包种类，“zip”, “tar”, “bztar”，“gztar”
root_dir： 要压缩的文件夹路径（默认当前目录）
owner： 用户，默认当前用户
group： 组，默认当前组
logger： 用于记录日志，通常是logging.Logger对象
1 def make_archive(base_name, format, root_dir=None, base_dir=None, verbose=0,
2 dry_run=0, owner=None, group=None, logger=None):
3 """Create an archive file (eg. zip or tar).
4
5 'base_name' is the name of the file to create, minus any format-specific
6 extension; 'format' is the archive format: one of "zip", "tar", "bztar"
7 or "gztar".
8
9 'root_dir' is a directory that will be the root directory of the
10 archive; ie. we typically chdir into 'root_dir' before creating the
11 archive. 'base_dir' is the directory where we start archiving from;
12 ie. 'base_dir' will be the common prefix of all files and
13 directories in the archive. 'root_dir' and 'base_dir' both default
14 to the current directory. Returns the name of the archive file.
15
16 'owner' and 'group' are used when creating a tar archive. By default,
17 uses the current owner and group.
18 """
19 save_cwd = os.getcwd()
20 if root_dir is not None:
21 if logger is not None:
22 logger.debug("changing into '%s'", root_dir)
23 base_name = os.path.abspath(base_name)
24 if not dry_run:
25 os.chdir(root_dir)
26
27 if base_dir is None:
28 base_dir = os.curdir
29
30 kwargs = {'dry_run': dry_run, 'logger': logger}
31
32 try:
33 format_info = _ARCHIVE_FORMATS[format]
34 except KeyError:
35 raise ValueError, "unknown archive format '%s'" % format
36
37 func = format_info[0]
38 for arg, val in format_info[1]:
39 kwargs[arg] = val
40
41 if format != 'zip':
42 kwargs['owner'] = owner
43 kwargs['group'] = group
44
45 try:
46 filename = func(base_name, base_dir, **kwargs)
47 finally:
48 if root_dir is not None:
49 if logger is not None:
50 logger.debug("changing back to '%s'", save_cwd)
51 os.chdir(save_cwd)
52
53 return filename
54
55 源码
源码
shutil 对压缩包的处理是调用 ZipFile 和 TarFile 两个模块来进行的，详细：
1 import zipfile
2
3 # 压缩
4 z = zipfile.ZipFile('laxi.zip', 'w')
5 z.write('a.log')
6 z.write('data.data')
7 z.close()
8
9 # 解压
10 z = zipfile.ZipFile('laxi.zip', 'r')
11 z.extractall()
12 z.close()
13
14 zipfile 压缩解压
15
16 zipfile 压缩解压
zipfile 压缩解压
1 import tarfile
2
3 # 压缩
4 tar = tarfile.open('your.tar','w')
5 tar.add('/Users/wupeiqi/PycharmProjects/bbs2.zip', arcname='bbs2.zip')
6 tar.add('/Users/wupeiqi/PycharmProjects/cmdb.zip', arcname='cmdb.zip')
7 tar.close()
8
9 # 解压
10 tar = tarfile.open('your.tar','r')
11 tar.extractall() # 可设置解压地址
12 tar.close()
13
14 tarfile 压缩解压
15
16 tarfile 压缩解压
tarfile 压缩解压
1 class ZipFile(object):
2 """ Class with methods to open, read, write, close, list zip files.
3
4 z = ZipFile(file, mode="r", compression=ZIP_STORED, allowZip64=False)
5
6 file: Either the path to the file, or a file-like object.
7 If it is a path, the file will be opened and closed by ZipFile.
8 mode: The mode can be either read "r", write "w" or append "a".
9 compression: ZIP_STORED (no compression) or ZIP_DEFLATED (requires zlib).
10 allowZip64: if True ZipFile will create files with ZIP64 extensions when
11 needed, otherwise it will raise an exception when this would
12 be necessary.
13
14 """
15
16 fp = None # Set here since __del__ checks it
17
18 def __init__(self, file, mode="r", compression=ZIP_STORED, allowZip64=False):
19 """Open the ZIP file with mode read "r", write "w" or append "a"."""
20 if mode not in ("r", "w", "a"):
21 raise RuntimeError('ZipFile() requires mode "r", "w", or "a"')
22
23 if compression == ZIP_STORED:
24 pass
25 elif compression == ZIP_DEFLATED:
26 if not zlib:
27 raise RuntimeError,\
28 "Compression requires the (missing) zlib module"
29 else:
30 raise RuntimeError, "That compression method is not supported"
31
32 self._allowZip64 = allowZip64
33 self._didModify = False
34 self.debug = 0 # Level of printing: 0 through 3
35 self.NameToInfo = {} # Find file info given name
36 self.filelist = [] # List of ZipInfo instances for archive
37 self.compression = compression # Method of compression
38 self.mode = key = mode.replace('b', '')[0]
39 self.pwd = None
40 self._comment = ''
41
42 # Check if we were passed a file-like object
43 if isinstance(file, basestring):
44 self._filePassed = 0
45 self.filename = file
46 modeDict = {'r' : 'rb', 'w': 'wb', 'a' : 'r+b'}
47 try:
48 self.fp = open(file, modeDict[mode])
49 except IOError:
50 if mode == 'a':
51 mode = key = 'w'
52 self.fp = open(file, modeDict[mode])
53 else:
54 raise
55 else:
56 self._filePassed = 1
57 self.fp = file
58 self.filename = getattr(file, 'name', None)
59
60 try:
61 if key == 'r':
62 self._RealGetContents()
63 elif key == 'w':
64 # set the modified flag so central directory gets written
65 # even if no files are added to the archive
66 self._didModify = True
67 elif key == 'a':
68 try:
69 # See if file is a zip file
70 self._RealGetContents()
71 # seek to start of directory and overwrite
72 self.fp.seek(self.start_dir, 0)
73 except BadZipfile:
74 # file is not a zip file, just append
75 self.fp.seek(0, 2)
76
77 # set the modified flag so central directory gets written
78 # even if no files are added to the archive
79 self._didModify = True
80 else:
81 raise RuntimeError('Mode must be "r", "w" or "a"')
82 except:
83 fp = self.fp
84 self.fp = None
85 if not self._filePassed:
86 fp.close()
87 raise
88
89 def __enter__(self):
90 return self
91
92 def __exit__(self, type, value, traceback):
93 self.close()
94
95 def _RealGetContents(self):
96 """Read in the table of contents for the ZIP file."""
97 fp = self.fp
98 try:
99 endrec = _EndRecData(fp)
100 except IOError:
101 raise BadZipfile("File is not a zip file")
102 if not endrec:
103 raise BadZipfile, "File is not a zip file"
104 if self.debug > 1:
105 print endrec
106 size_cd = endrec[_ECD_SIZE] # bytes in central directory
107 offset_cd = endrec[_ECD_OFFSET] # offset of central directory
108 self._comment = endrec[_ECD_COMMENT] # archive comment
109
110 # "concat" is zero, unless zip was concatenated to another file
111 concat = endrec[_ECD_LOCATION] - size_cd - offset_cd
112 if endrec[_ECD_SIGNATURE] == stringEndArchive64:
113 # If Zip64 extension structures are present, account for them
114 concat -= (sizeEndCentDir64 + sizeEndCentDir64Locator)
115
116 if self.debug > 2:
117 inferred = concat + offset_cd
118 print "given, inferred, offset", offset_cd, inferred, concat
119 # self.start_dir: Position of start of central directory
120 self.start_dir = offset_cd + concat
121 fp.seek(self.start_dir, 0)
122 data = fp.read(size_cd)
123 fp = cStringIO.StringIO(data)
124 total = 0
125 while total < size_cd:
126 centdir = fp.read(sizeCentralDir)
127 if len(centdir) != sizeCentralDir:
128 raise BadZipfile("Truncated central directory")
129 centdir = struct.unpack(structCentralDir, centdir)
130 if centdir[_CD_SIGNATURE] != stringCentralDir:
131 raise BadZipfile("Bad magic number for central directory")
132 if self.debug > 2:
133 print centdir
134 filename = fp.read(centdir[_CD_FILENAME_LENGTH])
135 # Create ZipInfo instance to store file information
136 x = ZipInfo(filename)
137 x.extra = fp.read(centdir[_CD_EXTRA_FIELD_LENGTH])
138 x.comment = fp.read(centdir[_CD_COMMENT_LENGTH])
139 x.header_offset = centdir[_CD_LOCAL_HEADER_OFFSET]
140 (x.create_version, x.create_system, x.extract_version, x.reserved,
141 x.flag_bits, x.compress_type, t, d,
142 x.CRC, x.compress_size, x.file_size) = centdir[1:12]
143 x.volume, x.internal_attr, x.external_attr = centdir[15:18]
144 # Convert date/time code to (year, month, day, hour, min, sec)
145 x._raw_time = t
146 x.date_time = ( (d>>9)+1980, (d>>5)&0xF, d&0x1F,
147 t>>11, (t>>5)&0x3F, (t&0x1F) * 2 )
148
149 x._decodeExtra()
150 x.header_offset = x.header_offset + concat
151 x.filename = x._decodeFilename()
152 self.filelist.append(x)
153 self.NameToInfo[x.filename] = x
154
155 # update total bytes read from central directory
156 total = (total + sizeCentralDir + centdir[_CD_FILENAME_LENGTH]
157 + centdir[_CD_EXTRA_FIELD_LENGTH]
158 + centdir[_CD_COMMENT_LENGTH])
159
160 if self.debug > 2:
161 print "total", total
162
163
164 def namelist(self):
165 """Return a list of file names in the archive."""
166 l = []
167 for data in self.filelist:
168 l.append(data.filename)
169 return l
170
171 def infolist(self):
172 """Return a list of class ZipInfo instances for files in the
173 archive."""
174 return self.filelist
175
176 def printdir(self):
177 """Print a table of contents for the zip file."""
178 print "%-46s %19s %12s" % ("File Name", "Modified ", "Size")
179 for zinfo in self.filelist:
180 date = "%d-%02d-%02d %02d:%02d:%02d" % zinfo.date_time[:6]
181 print "%-46s %s %12d" % (zinfo.filename, date, zinfo.file_size)
182
183 def testzip(self):
184 """Read all the files and check the CRC."""
185 chunk_size = 2 ** 20
186 for zinfo in self.filelist:
187 try:
188 # Read by chunks, to avoid an OverflowError or a
189 # MemoryError with very large embedded files.
190 with self.open(zinfo.filename, "r") as f:
191 while f.read(chunk_size): # Check CRC-32
192 pass
193 except BadZipfile:
194 return zinfo.filename
195
196 def getinfo(self, name):
197 """Return the instance of ZipInfo given 'name'."""
198 info = self.NameToInfo.get(name)
199 if info is None:
200 raise KeyError(
201 'There is no item named %r in the archive' % name)
202
203 return info
204
205 def setpassword(self, pwd):
206 """Set default password for encrypted files."""
207 self.pwd = pwd
208
209 @property
210 def comment(self):
211 """The comment text associated with the ZIP file."""
212 return self._comment
213
214 @comment.setter
215 def comment(self, comment):
216 # check for valid comment length
217 if len(comment) > ZIP_MAX_COMMENT:
218 import warnings
219 warnings.warn('Archive comment is too long; truncating to %d bytes'
220 % ZIP_MAX_COMMENT, stacklevel=2)
221 comment = comment[:ZIP_MAX_COMMENT]
222 self._comment = comment
223 self._didModify = True
224
225 def read(self, name, pwd=None):
226 """Return file bytes (as a string) for name."""
227 return self.open(name, "r", pwd).read()
228
229 def open(self, name, mode="r", pwd=None):
230 """Return file-like object for 'name'."""
231 if mode not in ("r", "U", "rU"):
232 raise RuntimeError, 'open() requires mode "r", "U", or "rU"'
233 if not self.fp:
234 raise RuntimeError, \
235 "Attempt to read ZIP archive that was already closed"
236
237 # Only open a new file for instances where we were not
238 # given a file object in the constructor
239 if self._filePassed:
240 zef_file = self.fp
241 should_close = False
242 else:
243 zef_file = open(self.filename, 'rb')
244 should_close = True
245
246 try:
247 # Make sure we have an info object
248 if isinstance(name, ZipInfo):
249 # 'name' is already an info object
250 zinfo = name
251 else:
252 # Get info object for name
253 zinfo = self.getinfo(name)
254
255 zef_file.seek(zinfo.header_offset, 0)
256
257 # Skip the file header:
258 fheader = zef_file.read(sizeFileHeader)
259 if len(fheader) != sizeFileHeader:
260 raise BadZipfile("Truncated file header")
261 fheader = struct.unpack(structFileHeader, fheader)
262 if fheader[_FH_SIGNATURE] != stringFileHeader:
263 raise BadZipfile("Bad magic number for file header")
264
265 fname = zef_file.read(fheader[_FH_FILENAME_LENGTH])
266 if fheader[_FH_EXTRA_FIELD_LENGTH]:
267 zef_file.read(fheader[_FH_EXTRA_FIELD_LENGTH])
268
269 if fname != zinfo.orig_filename:
270 raise BadZipfile, \
271 'File name in directory "%s" and header "%s" differ.' % (
272 zinfo.orig_filename, fname)
273
274 # check for encrypted flag & handle password
275 is_encrypted = zinfo.flag_bits & 0x1
276 zd = None
277 if is_encrypted:
278 if not pwd:
279 pwd = self.pwd
280 if not pwd:
281 raise RuntimeError, "File %s is encrypted, " \
282 "password required for extraction" % name
283
284 zd = _ZipDecrypter(pwd)
285 # The first 12 bytes in the cypher stream is an encryption header
286 # used to strengthen the algorithm. The first 11 bytes are
287 # completely random, while the 12th contains the MSB of the CRC,
288 # or the MSB of the file time depending on the header type
289 # and is used to check the correctness of the password.
290 bytes = zef_file.read(12)
291 h = map(zd, bytes[0:12])
292 if zinfo.flag_bits & 0x8:
293 # compare against the file type from extended local headers
294 check_byte = (zinfo._raw_time >> 8) & 0xff
295 else:
296 # compare against the CRC otherwise
297 check_byte = (zinfo.CRC >> 24) & 0xff
298 if ord(h[11]) != check_byte:
299 raise RuntimeError("Bad password for file", name)
300
301 return ZipExtFile(zef_file, mode, zinfo, zd,
302 close_fileobj=should_close)
303 except:
304 if should_close:
305 zef_file.close()
306 raise
307
308 def extract(self, member, path=None, pwd=None):
309 """Extract a member from the archive to the current working directory,
310 using its full name. Its file information is extracted as accurately
311 as possible. `member' may be a filename or a ZipInfo object. You can
312 specify a different directory using `path'.
313 """
314 if not isinstance(member, ZipInfo):
315 member = self.getinfo(member)
316
317 if path is None:
318 path = os.getcwd()
319
320 return self._extract_member(member, path, pwd)
321
322 def extractall(self, path=None, members=None, pwd=None):
323 """Extract all members from the archive to the current working
324 directory. `path' specifies a different directory to extract to.
325 `members' is optional and must be a subset of the list returned
326 by namelist().
327 """
328 if members is None:
329 members = self.namelist()
330
331 for zipinfo in members:
332 self.extract(zipinfo, path, pwd)
333
334 def _extract_member(self, member, targetpath, pwd):
335 """Extract the ZipInfo object 'member' to a physical
336 file on the path targetpath.
337 """
338 # build the destination pathname, replacing
339 # forward slashes to platform specific separators.
340 arcname = member.filename.replace('/', os.path.sep)
341
342 if os.path.altsep:
343 arcname = arcname.replace(os.path.altsep, os.path.sep)
344 # interpret absolute pathname as relative, remove drive letter or
345 # UNC path, redundant separators, "." and ".." components.
346 arcname = os.path.splitdrive(arcname)[1]
347 arcname = os.path.sep.join(x for x in arcname.split(os.path.sep)
348 if x not in ('', os.path.curdir, os.path.pardir))
349 if os.path.sep == '\\':
350 # filter illegal characters on Windows
351 illegal = ':<>|"?*'
352 if isinstance(arcname, unicode):
353 table = {ord(c): ord('_') for c in illegal}
354 else:
355 table = string.maketrans(illegal, '_' * len(illegal))
356 arcname = arcname.translate(table)
357 # remove trailing dots
358 arcname = (x.rstrip('.') for x in arcname.split(os.path.sep))
359 arcname = os.path.sep.join(x for x in arcname if x)
360
361 targetpath = os.path.join(targetpath, arcname)
362 targetpath = os.path.normpath(targetpath)
363
364 # Create all upper directories if necessary.
365 upperdirs = os.path.dirname(targetpath)
366 if upperdirs and not os.path.exists(upperdirs):
367 os.makedirs(upperdirs)
368
369 if member.filename[-1] == '/':
370 if not os.path.isdir(targetpath):
371 os.mkdir(targetpath)
372 return targetpath
373
374 with self.open(member, pwd=pwd) as source, \
375 file(targetpath, "wb") as target:
376 shutil.copyfileobj(source, target)
377
378 return targetpath
379
380 def _writecheck(self, zinfo):
381 """Check for errors before writing a file to the archive."""
382 if zinfo.filename in self.NameToInfo:
383 import warnings
384 warnings.warn('Duplicate name: %r' % zinfo.filename, stacklevel=3)
385 if self.mode not in ("w", "a"):
386 raise RuntimeError, 'write() requires mode "w" or "a"'
387 if not self.fp:
388 raise RuntimeError, \
389 "Attempt to write ZIP archive that was already closed"
390 if zinfo.compress_type == ZIP_DEFLATED and not zlib:
391 raise RuntimeError, \
392 "Compression requires the (missing) zlib module"
393 if zinfo.compress_type not in (ZIP_STORED, ZIP_DEFLATED):
394 raise RuntimeError, \
395 "That compression method is not supported"
396 if not self._allowZip64:
397 requires_zip64 = None
398 if len(self.filelist) >= ZIP_FILECOUNT_LIMIT:
399 requires_zip64 = "Files count"
400 elif zinfo.file_size > ZIP64_LIMIT:
401 requires_zip64 = "Filesize"
402 elif zinfo.header_offset > ZIP64_LIMIT:
403 requires_zip64 = "Zipfile size"
404 if requires_zip64:
405 raise LargeZipFile(requires_zip64 +
406 " would require ZIP64 extensions")
407
408 def write(self, filename, arcname=None, compress_type=None):
409 """Put the bytes from filename into the archive under the name
410 arcname."""
411 if not self.fp:
412 raise RuntimeError(
413 "Attempt to write to ZIP archive that was already closed")
414
415 st = os.stat(filename)
416 isdir = stat.S_ISDIR(st.st_mode)
417 mtime = time.localtime(st.st_mtime)
418 date_time = mtime[0:6]
419 # Create ZipInfo instance to store file information
420 if arcname is None:
421 arcname = filename
422 arcname = os.path.normpath(os.path.splitdrive(arcname)[1])
423 while arcname[0] in (os.sep, os.altsep):
424 arcname = arcname[1:]
425 if isdir:
426 arcname += '/'
427 zinfo = ZipInfo(arcname, date_time)
428 zinfo.external_attr = (st[0] & 0xFFFF) << 16L # Unix attributes
429 if compress_type is None:
430 zinfo.compress_type = self.compression
431 else:
432 zinfo.compress_type = compress_type
433
434 zinfo.file_size = st.st_size
435 zinfo.flag_bits = 0x00
436 zinfo.header_offset = self.fp.tell() # Start of header bytes
437
438 self._writecheck(zinfo)
439 self._didModify = True
440
441 if isdir:
442 zinfo.file_size = 0
443 zinfo.compress_size = 0
444 zinfo.CRC = 0
445 zinfo.external_attr |= 0x10 # MS-DOS directory flag
446 self.filelist.append(zinfo)
447 self.NameToInfo[zinfo.filename] = zinfo
448 self.fp.write(zinfo.FileHeader(False))
449 return
450
451 with open(filename, "rb") as fp:
452 # Must overwrite CRC and sizes with correct data later
453 zinfo.CRC = CRC = 0
454 zinfo.compress_size = compress_size = 0
455 # Compressed size can be larger than uncompressed size
456 zip64 = self._allowZip64 and \
457 zinfo.file_size * 1.05 > ZIP64_LIMIT
458 self.fp.write(zinfo.FileHeader(zip64))
459 if zinfo.compress_type == ZIP_DEFLATED:
460 cmpr = zlib.compressobj(zlib.Z_DEFAULT_COMPRESSION,
461 zlib.DEFLATED, -15)
462 else:
463 cmpr = None
464 file_size = 0
465 while 1:
466 buf = fp.read(1024 * 8)
467 if not buf:
468 break
469 file_size = file_size + len(buf)
470 CRC = crc32(buf, CRC) & 0xffffffff
471 if cmpr:
472 buf = cmpr.compress(buf)
473 compress_size = compress_size + len(buf)
474 self.fp.write(buf)
475 if cmpr:
476 buf = cmpr.flush()
477 compress_size = compress_size + len(buf)
478 self.fp.write(buf)
479 zinfo.compress_size = compress_size
480 else:
481 zinfo.compress_size = file_size
482 zinfo.CRC = CRC
483 zinfo.file_size = file_size
484 if not zip64 and self._allowZip64:
485 if file_size > ZIP64_LIMIT:
486 raise RuntimeError('File size has increased during compressing')
487 if compress_size > ZIP64_LIMIT:
488 raise RuntimeError('Compressed size larger than uncompressed size')
489 # Seek backwards and write file header (which will now include
490 # correct CRC and file sizes)
491 position = self.fp.tell() # Preserve current position in file
492 self.fp.seek(zinfo.header_offset, 0)
493 self.fp.write(zinfo.FileHeader(zip64))
494 self.fp.seek(position, 0)
495 self.filelist.append(zinfo)
496 self.NameToInfo[zinfo.filename] = zinfo
497
498 def writestr(self, zinfo_or_arcname, bytes, compress_type=None):
499 """Write a file into the archive. The contents is the string
500 'bytes'. 'zinfo_or_arcname' is either a ZipInfo instance or
501 the name of the file in the archive."""
502 if not isinstance(zinfo_or_arcname, ZipInfo):
503 zinfo = ZipInfo(filename=zinfo_or_arcname,
504 date_time=time.localtime(time.time())[:6])
505
506 zinfo.compress_type = self.compression
507 if zinfo.filename[-1] == '/':
508 zinfo.external_attr = 0o40775 << 16 # drwxrwxr-x
509 zinfo.external_attr |= 0x10 # MS-DOS directory flag
510 else:
511 zinfo.external_attr = 0o600 << 16 # ?rw-------
512 else:
513 zinfo = zinfo_or_arcname
514
515 if not self.fp:
516 raise RuntimeError(
517 "Attempt to write to ZIP archive that was already closed")
518
519 if compress_type is not None:
520 zinfo.compress_type = compress_type
521
522 zinfo.file_size = len(bytes) # Uncompressed size
523 zinfo.header_offset = self.fp.tell() # Start of header bytes
524 self._writecheck(zinfo)
525 self._didModify = True
526 zinfo.CRC = crc32(bytes) & 0xffffffff # CRC-32 checksum
527 if zinfo.compress_type == ZIP_DEFLATED:
528 co = zlib.compressobj(zlib.Z_DEFAULT_COMPRESSION,
529 zlib.DEFLATED, -15)
530 bytes = co.compress(bytes) + co.flush()
531 zinfo.compress_size = len(bytes) # Compressed size
532 else:
533 zinfo.compress_size = zinfo.file_size
534 zip64 = zinfo.file_size > ZIP64_LIMIT or \
535 zinfo.compress_size > ZIP64_LIMIT
536 if zip64 and not self._allowZip64:
537 raise LargeZipFile("Filesize would require ZIP64 extensions")
538 self.fp.write(zinfo.FileHeader(zip64))
539 self.fp.write(bytes)
540 if zinfo.flag_bits & 0x08:
541 # Write CRC and file sizes after the file data
542 fmt = '<LQQ' if zip64 else '<LLL'
543 self.fp.write(struct.pack(fmt, zinfo.CRC, zinfo.compress_size,
544 zinfo.file_size))
545 self.fp.flush()
546 self.filelist.append(zinfo)
547 self.NameToInfo[zinfo.filename] = zinfo
548
549 def __del__(self):
550 """Call the "close()" method in case the user forgot."""
551 self.close()
552
553 def close(self):
554 """Close the file, and for mode "w" and "a" write the ending
555 records."""
556 if self.fp is None:
557 return
558
559 try:
560 if self.mode in ("w", "a") and self._didModify: # write ending records
561 pos1 = self.fp.tell()
562 for zinfo in self.filelist: # write central directory
563 dt = zinfo.date_time
564 dosdate = (dt[0] - 1980) << 9 | dt[1] << 5 | dt[2]
565 dostime = dt[3] << 11 | dt[4] << 5 | (dt[5] // 2)
566 extra = []
567 if zinfo.file_size > ZIP64_LIMIT \
568 or zinfo.compress_size > ZIP64_LIMIT:
569 extra.append(zinfo.file_size)
570 extra.append(zinfo.compress_size)
571 file_size = 0xffffffff
572 compress_size = 0xffffffff
573 else:
574 file_size = zinfo.file_size
575 compress_size = zinfo.compress_size
576
577 if zinfo.header_offset > ZIP64_LIMIT:
578 extra.append(zinfo.header_offset)
579 header_offset = 0xffffffffL
580 else:
581 header_offset = zinfo.header_offset
582
583 extra_data = zinfo.extra
584 if extra:
585 # Append a ZIP64 field to the extra's
586 extra_data = struct.pack(
587 '<HH' + 'Q'*len(extra),
588 1, 8*len(extra), *extra) + extra_data
589
590 extract_version = max(45, zinfo.extract_version)
591 create_version = max(45, zinfo.create_version)
592 else:
593 extract_version = zinfo.extract_version
594 create_version = zinfo.create_version
595
596 try:
597 filename, flag_bits = zinfo._encodeFilenameFlags()
598 centdir = struct.pack(structCentralDir,
599 stringCentralDir, create_version,
600 zinfo.create_system, extract_version, zinfo.reserved,
601 flag_bits, zinfo.compress_type, dostime, dosdate,
602 zinfo.CRC, compress_size, file_size,
603 len(filename), len(extra_data), len(zinfo.comment),
604 0, zinfo.internal_attr, zinfo.external_attr,
605 header_offset)
606 except DeprecationWarning:
607 print >>sys.stderr, (structCentralDir,
608 stringCentralDir, create_version,
609 zinfo.create_system, extract_version, zinfo.reserved,
610 zinfo.flag_bits, zinfo.compress_type, dostime, dosdate,
611 zinfo.CRC, compress_size, file_size,
612 len(zinfo.filename), len(extra_data), len(zinfo.comment),
613 0, zinfo.internal_attr, zinfo.external_attr,
614 header_offset)
615 raise
616 self.fp.write(centdir)
617 self.fp.write(filename)
618 self.fp.write(extra_data)
619 self.fp.write(zinfo.comment)
620
621 pos2 = self.fp.tell()
622 # Write end-of-zip-archive record
623 centDirCount = len(self.filelist)
624 centDirSize = pos2 - pos1
625 centDirOffset = pos1
626 requires_zip64 = None
627 if centDirCount > ZIP_FILECOUNT_LIMIT:
628 requires_zip64 = "Files count"
629 elif centDirOffset > ZIP64_LIMIT:
630 requires_zip64 = "Central directory offset"
631 elif centDirSize > ZIP64_LIMIT:
632 requires_zip64 = "Central directory size"
633 if requires_zip64:
634 # Need to write the ZIP64 end-of-archive records
635 if not self._allowZip64:
636 raise LargeZipFile(requires_zip64 +
637 " would require ZIP64 extensions")
638 zip64endrec = struct.pack(
639 structEndArchive64, stringEndArchive64,
640 44, 45, 45, 0, 0, centDirCount, centDirCount,
641 centDirSize, centDirOffset)
642 self.fp.write(zip64endrec)
643
644 zip64locrec = struct.pack(
645 structEndArchive64Locator,
646 stringEndArchive64Locator, 0, pos2, 1)
647 self.fp.write(zip64locrec)
648 centDirCount = min(centDirCount, 0xFFFF)
649 centDirSize = min(centDirSize, 0xFFFFFFFF)
650 centDirOffset = min(centDirOffset, 0xFFFFFFFF)
651
652 endrec = struct.pack(structEndArchive, stringEndArchive,
653 0, 0, centDirCount, centDirCount,
654 centDirSize, centDirOffset, len(self._comment))
655 self.fp.write(endrec)
656 self.fp.write(self._comment)
657 self.fp.flush()
658 finally:
659 fp = self.fp
660 self.fp = None
661 if not self._filePassed:
662 fp.close()
663
664 ZipFile
665
666 ZipFile 源码
ZipFile 源码
1 class TarFile(object):
2 """The TarFile Class provides an interface to tar archives.
3 """
4
5 debug = 0 # May be set from 0 (no msgs) to 3 (all msgs)
6
7 dereference = False # If true, add content of linked file to the
8 # tar file, else the link.
9
10 ignore_zeros = False # If true, skips empty or invalid blocks and
11 # continues processing.
12
13 errorlevel = 1 # If 0, fatal errors only appear in debug
14 # messages (if debug >= 0). If > 0, errors
15 # are passed to the caller as exceptions.
16
17 format = DEFAULT_FORMAT # The format to use when creating an archive.
18
19 encoding = ENCODING # Encoding for 8-bit character strings.
20
21 errors = None # Error handler for unicode conversion.
22
23 tarinfo = TarInfo # The default TarInfo class to use.
24
25 fileobject = ExFileObject # The default ExFileObject class to use.
26
27 def __init__(self, name=None, mode="r", fileobj=None, format=None,
28 tarinfo=None, dereference=None, ignore_zeros=None, encoding=None,
29 errors=None, pax_headers=None, debug=None, errorlevel=None):
30 """Open an (uncompressed) tar archive `name'. `mode' is either 'r' to
31 read from an existing archive, 'a' to append data to an existing
32 file or 'w' to create a new file overwriting an existing one. `mode'
33 defaults to 'r'.
34 If `fileobj' is given, it is used for reading or writing data. If it
35 can be determined, `mode' is overridden by `fileobj's mode.
36 `fileobj' is not closed, when TarFile is closed.
37 """
38 modes = {"r": "rb", "a": "r+b", "w": "wb"}
39 if mode not in modes:
40 raise ValueError("mode must be 'r', 'a' or 'w'")
41 self.mode = mode
42 self._mode = modes[mode]
43
44 if not fileobj:
45 if self.mode == "a" and not os.path.exists(name):
46 # Create nonexistent files in append mode.
47 self.mode = "w"
48 self._mode = "wb"
49 fileobj = bltn_open(name, self._mode)
50 self._extfileobj = False
51 else:
52 if name is None and hasattr(fileobj, "name"):
53 name = fileobj.name
54 if hasattr(fileobj, "mode"):
55 self._mode = fileobj.mode
56 self._extfileobj = True
57 self.name = os.path.abspath(name) if name else None
58 self.fileobj = fileobj
59
60 # Init attributes.
61 if format is not None:
62 self.format = format
63 if tarinfo is not None:
64 self.tarinfo = tarinfo
65 if dereference is not None:
66 self.dereference = dereference
67 if ignore_zeros is not None:
68 self.ignore_zeros = ignore_zeros
69 if encoding is not None:
70 self.encoding = encoding
71
72 if errors is not None:
73 self.errors = errors
74 elif mode == "r":
75 self.errors = "utf-8"
76 else:
77 self.errors = "strict"
78
79 if pax_headers is not None and self.format == PAX_FORMAT:
80 self.pax_headers = pax_headers
81 else:
82 self.pax_headers = {}
83
84 if debug is not None:
85 self.debug = debug
86 if errorlevel is not None:
87 self.errorlevel = errorlevel
88
89 # Init datastructures.
90 self.closed = False
91 self.members = [] # list of members as TarInfo objects
92 self._loaded = False # flag if all members have been read
93 self.offset = self.fileobj.tell()
94 # current position in the archive file
95 self.inodes = {} # dictionary caching the inodes of
96 # archive members already added
97
98 try:
99 if self.mode == "r":
100 self.firstmember = None
101 self.firstmember = self.next()
102
103 if self.mode == "a":
104 # Move to the end of the archive,
105 # before the first empty block.
106 while True:
107 self.fileobj.seek(self.offset)
108 try:
109 tarinfo = self.tarinfo.fromtarfile(self)
110 self.members.append(tarinfo)
111 except EOFHeaderError:
112 self.fileobj.seek(self.offset)
113 break
114 except HeaderError, e:
115 raise ReadError(str(e))
116
117 if self.mode in "aw":
118 self._loaded = True
119
120 if self.pax_headers:
121 buf = self.tarinfo.create_pax_global_header(self.pax_headers.copy())
122 self.fileobj.write(buf)
123 self.offset += len(buf)
124 except:
125 if not self._extfileobj:
126 self.fileobj.close()
127 self.closed = True
128 raise
129
130 def _getposix(self):
131 return self.format == USTAR_FORMAT
132 def _setposix(self, value):
133 import warnings
134 warnings.warn("use the format attribute instead", DeprecationWarning,
135 2)
136 if value:
137 self.format = USTAR_FORMAT
138 else:
139 self.format = GNU_FORMAT
140 posix = property(_getposix, _setposix)
141
142 #--------------------------------------------------------------------------
143 # Below are the classmethods which act as alternate constructors to the
144 # TarFile class. The open() method is the only one that is needed for
145 # public use; it is the "super"-constructor and is able to select an
146 # adequate "sub"-constructor for a particular compression using the mapping
147 # from OPEN_METH.
148 #
149 # This concept allows one to subclass TarFile without losing the comfort of
150 # the super-constructor. A sub-constructor is registered and made available
151 # by adding it to the mapping in OPEN_METH.
152
153 @classmethod
154 def open(cls, name=None, mode="r", fileobj=None, bufsize=RECORDSIZE, **kwargs):
155 """Open a tar archive for reading, writing or appending. Return
156 an appropriate TarFile class.
157
158 mode:
159 'r' or 'r:*' open for reading with transparent compression
160 'r:' open for reading exclusively uncompressed
161 'r:gz' open for reading with gzip compression
162 'r:bz2' open for reading with bzip2 compression
163 'a' or 'a:' open for appending, creating the file if necessary
164 'w' or 'w:' open for writing without compression
165 'w:gz' open for writing with gzip compression
166 'w:bz2' open for writing with bzip2 compression
167
168 'r|*' open a stream of tar blocks with transparent compression
169 'r|' open an uncompressed stream of tar blocks for reading
170 'r|gz' open a gzip compressed stream of tar blocks
171 'r|bz2' open a bzip2 compressed stream of tar blocks
172 'w|' open an uncompressed stream for writing
173 'w|gz' open a gzip compressed stream for writing
174 'w|bz2' open a bzip2 compressed stream for writing
175 """
176
177 if not name and not fileobj:
178 raise ValueError("nothing to open")
179
180 if mode in ("r", "r:*"):
181 # Find out which *open() is appropriate for opening the file.
182 for comptype in cls.OPEN_METH:
183 func = getattr(cls, cls.OPEN_METH[comptype])
184 if fileobj is not None:
185 saved_pos = fileobj.tell()
186 try:
187 return func(name, "r", fileobj, **kwargs)
188 except (ReadError, CompressionError), e:
189 if fileobj is not None:
190 fileobj.seek(saved_pos)
191 continue
192 raise ReadError("file could not be opened successfully")
193
194 elif ":" in mode:
195 filemode, comptype = mode.split(":", 1)
196 filemode = filemode or "r"
197 comptype = comptype or "tar"
198
199 # Select the *open() function according to
200 # given compression.
201 if comptype in cls.OPEN_METH:
202 func = getattr(cls, cls.OPEN_METH[comptype])
203 else:
204 raise CompressionError("unknown compression type %r" % comptype)
205 return func(name, filemode, fileobj, **kwargs)
206
207 elif "|" in mode:
208 filemode, comptype = mode.split("|", 1)
209 filemode = filemode or "r"
210 comptype = comptype or "tar"
211
212 if filemode not in ("r", "w"):
213 raise ValueError("mode must be 'r' or 'w'")
214
215 stream = _Stream(name, filemode, comptype, fileobj, bufsize)
216 try:
217 t = cls(name, filemode, stream, **kwargs)
218 except:
219 stream.close()
220 raise
221 t._extfileobj = False
222 return t
223
224 elif mode in ("a", "w"):
225 return cls.taropen(name, mode, fileobj, **kwargs)
226
227 raise ValueError("undiscernible mode")
228
229 @classmethod
230 def taropen(cls, name, mode="r", fileobj=None, **kwargs):
231 """Open uncompressed tar archive name for reading or writing.
232 """
233 if mode not in ("r", "a", "w"):
234 raise ValueError("mode must be 'r', 'a' or 'w'")
235 return cls(name, mode, fileobj, **kwargs)
236
237 @classmethod
238 def gzopen(cls, name, mode="r", fileobj=None, compresslevel=9, **kwargs):
239 """Open gzip compressed tar archive name for reading or writing.
240 Appending is not allowed.
241 """
242 if mode not in ("r", "w"):
243 raise ValueError("mode must be 'r' or 'w'")
244
245 try:
246 import gzip
247 gzip.GzipFile
248 except (ImportError, AttributeError):
249 raise CompressionError("gzip module is not available")
250
251 try:
252 fileobj = gzip.GzipFile(name, mode, compresslevel, fileobj)
253 except OSError:
254 if fileobj is not None and mode == 'r':
255 raise ReadError("not a gzip file")
256 raise
257
258 try:
259 t = cls.taropen(name, mode, fileobj, **kwargs)
260 except IOError:
261 fileobj.close()
262 if mode == 'r':
263 raise ReadError("not a gzip file")
264 raise
265 except:
266 fileobj.close()
267 raise
268 t._extfileobj = False
269 return t
270
271 @classmethod
272 def bz2open(cls, name, mode="r", fileobj=None, compresslevel=9, **kwargs):
273 """Open bzip2 compressed tar archive name for reading or writing.
274 Appending is not allowed.
275 """
276 if mode not in ("r", "w"):
277 raise ValueError("mode must be 'r' or 'w'.")
278
279 try:
280 import bz2
281 except ImportError:
282 raise CompressionError("bz2 module is not available")
283
284 if fileobj is not None:
285 fileobj = _BZ2Proxy(fileobj, mode)
286 else:
287 fileobj = bz2.BZ2File(name, mode, compresslevel=compresslevel)
288
289 try:
290 t = cls.taropen(name, mode, fileobj, **kwargs)
291 except (IOError, EOFError):
292 fileobj.close()
293 if mode == 'r':
294 raise ReadError("not a bzip2 file")
295 raise
296 except:
297 fileobj.close()
298 raise
299 t._extfileobj = False
300 return t
301
302 # All *open() methods are registered here.
303 OPEN_METH = {
304 "tar": "taropen", # uncompressed tar
305 "gz": "gzopen", # gzip compressed tar
306 "bz2": "bz2open" # bzip2 compressed tar
307 }
308
309 #--------------------------------------------------------------------------
310 # The public methods which TarFile provides:
311
312 def close(self):
313 """Close the TarFile. In write-mode, two finishing zero blocks are
314 appended to the archive.
315 """
316 if self.closed:
317 return
318
319 if self.mode in "aw":
320 self.fileobj.write(NUL * (BLOCKSIZE * 2))
321 self.offset += (BLOCKSIZE * 2)
322 # fill up the end with zero-blocks
323 # (like option -b20 for tar does)
324 blocks, remainder = divmod(self.offset, RECORDSIZE)
325 if remainder > 0:
326 self.fileobj.write(NUL * (RECORDSIZE - remainder))
327
328 if not self._extfileobj:
329 self.fileobj.close()
330 self.closed = True
331
332 def getmember(self, name):
333 """Return a TarInfo object for member `name'. If `name' can not be
334 found in the archive, KeyError is raised. If a member occurs more
335 than once in the archive, its last occurrence is assumed to be the
336 most up-to-date version.
337 """
338 tarinfo = self._getmember(name)
339 if tarinfo is None:
340 raise KeyError("filename %r not found" % name)
341 return tarinfo
342
343 def getmembers(self):
344 """Return the members of the archive as a list of TarInfo objects. The
345 list has the same order as the members in the archive.
346 """
347 self._check()
348 if not self._loaded: # if we want to obtain a list of
349 self._load() # all members, we first have to
350 # scan the whole archive.
351 return self.members
352
353 def getnames(self):
354 """Return the members of the archive as a list of their names. It has
355 the same order as the list returned by getmembers().
356 """
357 return [tarinfo.name for tarinfo in self.getmembers()]
358
359 def gettarinfo(self, name=None, arcname=None, fileobj=None):
360 """Create a TarInfo object for either the file `name' or the file
361 object `fileobj' (using os.fstat on its file descriptor). You can
362 modify some of the TarInfo's attributes before you add it using
363 addfile(). If given, `arcname' specifies an alternative name for the
364 file in the archive.
365 """
366 self._check("aw")
367
368 # When fileobj is given, replace name by
369 # fileobj's real name.
370 if fileobj is not None:
371 name = fileobj.name
372
373 # Building the name of the member in the archive.
374 # Backward slashes are converted to forward slashes,
375 # Absolute paths are turned to relative paths.
376 if arcname is None:
377 arcname = name
378 drv, arcname = os.path.splitdrive(arcname)
379 arcname = arcname.replace(os.sep, "/")
380 arcname = arcname.lstrip("/")
381
382 # Now, fill the TarInfo object with
383 # information specific for the file.
384 tarinfo = self.tarinfo()
385 tarinfo.tarfile = self
386
387 # Use os.stat or os.lstat, depending on platform
388 # and if symlinks shall be resolved.
389 if fileobj is None:
390 if hasattr(os, "lstat") and not self.dereference:
391 statres = os.lstat(name)
392 else:
393 statres = os.stat(name)
394 else:
395 statres = os.fstat(fileobj.fileno())
396 linkname = ""
397
398 stmd = statres.st_mode
399 if stat.S_ISREG(stmd):
400 inode = (statres.st_ino, statres.st_dev)
401 if not self.dereference and statres.st_nlink > 1 and \
402 inode in self.inodes and arcname != self.inodes[inode]:
403 # Is it a hardlink to an already
404 # archived file?
405 type = LNKTYPE
406 linkname = self.inodes[inode]
407 else:
408 # The inode is added only if its valid.
409 # For win32 it is always 0.
410 type = REGTYPE
411 if inode[0]:
412 self.inodes[inode] = arcname
413 elif stat.S_ISDIR(stmd):
414 type = DIRTYPE
415 elif stat.S_ISFIFO(stmd):
416 type = FIFOTYPE
417 elif stat.S_ISLNK(stmd):
418 type = SYMTYPE
419 linkname = os.readlink(name)
420 elif stat.S_ISCHR(stmd):
421 type = CHRTYPE
422 elif stat.S_ISBLK(stmd):
423 type = BLKTYPE
424 else:
425 return None
426
427 # Fill the TarInfo object with all
428 # information we can get.
429 tarinfo.name = arcname
430 tarinfo.mode = stmd
431 tarinfo.uid = statres.st_uid
432 tarinfo.gid = statres.st_gid
433 if type == REGTYPE:
434 tarinfo.size = statres.st_size
435 else:
436 tarinfo.size = 0L
437 tarinfo.mtime = statres.st_mtime
438 tarinfo.type = type
439 tarinfo.linkname = linkname
440 if pwd:
441 try:
442 tarinfo.uname = pwd.getpwuid(tarinfo.uid)[0]
443 except KeyError:
444 pass
445 if grp:
446 try:
447 tarinfo.gname = grp.getgrgid(tarinfo.gid)[0]
448 except KeyError:
449 pass
450
451 if type in (CHRTYPE, BLKTYPE):
452 if hasattr(os, "major") and hasattr(os, "minor"):
453 tarinfo.devmajor = os.major(statres.st_rdev)
454 tarinfo.devminor = os.minor(statres.st_rdev)
455 return tarinfo
456
457 def list(self, verbose=True):
458 """Print a table of contents to sys.stdout. If `verbose' is False, only
459 the names of the members are printed. If it is True, an `ls -l'-like
460 output is produced.
461 """
462 self._check()
463
464 for tarinfo in self:
465 if verbose:
466 print filemode(tarinfo.mode),
467 print "%s/%s" % (tarinfo.uname or tarinfo.uid,
468 tarinfo.gname or tarinfo.gid),
469 if tarinfo.ischr() or tarinfo.isblk():
470 print "%10s" % ("%d,%d" \
471 % (tarinfo.devmajor, tarinfo.devminor)),
472 else:
473 print "%10d" % tarinfo.size,
474 print "%d-%02d-%02d %02d:%02d:%02d" \
475 % time.localtime(tarinfo.mtime)[:6],
476
477 print tarinfo.name + ("/" if tarinfo.isdir() else ""),
478
479 if verbose:
480 if tarinfo.issym():
481 print "->", tarinfo.linkname,
482 if tarinfo.islnk():
483 print "link to", tarinfo.linkname,
484 print
485
486 def add(self, name, arcname=None, recursive=True, exclude=None, filter=None):
487 """Add the file `name' to the archive. `name' may be any type of file
488 (directory, fifo, symbolic link, etc.). If given, `arcname'
489 specifies an alternative name for the file in the archive.
490 Directories are added recursively by default. This can be avoided by
491 setting `recursive' to False. `exclude' is a function that should
492 return True for each filename to be excluded. `filter' is a function
493 that expects a TarInfo object argument and returns the changed
494 TarInfo object, if it returns None the TarInfo object will be
495 excluded from the archive.
496 """
497 self._check("aw")
498
499 if arcname is None:
500 arcname = name
501
502 # Exclude pathnames.
503 if exclude is not None:
504 import warnings
505 warnings.warn("use the filter argument instead",
506 DeprecationWarning, 2)
507 if exclude(name):
508 self._dbg(2, "tarfile: Excluded %r" % name)
509 return
510
511 # Skip if somebody tries to archive the archive...
512 if self.name is not None and os.path.abspath(name) == self.name:
513 self._dbg(2, "tarfile: Skipped %r" % name)
514 return
515
516 self._dbg(1, name)
517
518 # Create a TarInfo object from the file.
519 tarinfo = self.gettarinfo(name, arcname)
520
521 if tarinfo is None:
522 self._dbg(1, "tarfile: Unsupported type %r" % name)
523 return
524
525 # Change or exclude the TarInfo object.
526 if filter is not None:
527 tarinfo = filter(tarinfo)
528 if tarinfo is None:
529 self._dbg(2, "tarfile: Excluded %r" % name)
530 return
531
532 # Append the tar header and data to the archive.
533 if tarinfo.isreg():
534 with bltn_open(name, "rb") as f:
535 self.addfile(tarinfo, f)
536
537 elif tarinfo.isdir():
538 self.addfile(tarinfo)
539 if recursive:
540 for f in os.listdir(name):
541 self.add(os.path.join(name, f), os.path.join(arcname, f),
542 recursive, exclude, filter)
543
544 else:
545 self.addfile(tarinfo)
546
547 def addfile(self, tarinfo, fileobj=None):
548 """Add the TarInfo object `tarinfo' to the archive. If `fileobj' is
549 given, tarinfo.size bytes are read from it and added to the archive.
550 You can create TarInfo objects using gettarinfo().
551 On Windows platforms, `fileobj' should always be opened with mode
552 'rb' to avoid irritation about the file size.
553 """
554 self._check("aw")
555
556 tarinfo = copy.copy(tarinfo)
557
558 buf = tarinfo.tobuf(self.format, self.encoding, self.errors)
559 self.fileobj.write(buf)
560 self.offset += len(buf)
561
562 # If there's data to follow, append it.
563 if fileobj is not None:
564 copyfileobj(fileobj, self.fileobj, tarinfo.size)
565 blocks, remainder = divmod(tarinfo.size, BLOCKSIZE)
566 if remainder > 0:
567 self.fileobj.write(NUL * (BLOCKSIZE - remainder))
568 blocks += 1
569 self.offset += blocks * BLOCKSIZE
570
571 self.members.append(tarinfo)
572
573 def extractall(self, path=".", members=None):
574 """Extract all members from the archive to the current working
575 directory and set owner, modification time and permissions on
576 directories afterwards. `path' specifies a different directory
577 to extract to. `members' is optional and must be a subset of the
578 list returned by getmembers().
579 """
580 directories = []
581
582 if members is None:
583 members = self
584
585 for tarinfo in members:
586 if tarinfo.isdir():
587 # Extract directories with a safe mode.
588 directories.append(tarinfo)
589 tarinfo = copy.copy(tarinfo)
590 tarinfo.mode = 0700
591 self.extract(tarinfo, path)
592
593 # Reverse sort directories.
594 directories.sort(key=operator.attrgetter('name'))
595 directories.reverse()
596
597 # Set correct owner, mtime and filemode on directories.
598 for tarinfo in directories:
599 dirpath = os.path.join(path, tarinfo.name)
600 try:
601 self.chown(tarinfo, dirpath)
602 self.utime(tarinfo, dirpath)
603 self.chmod(tarinfo, dirpath)
604 except ExtractError, e:
605 if self.errorlevel > 1:
606 raise
607 else:
608 self._dbg(1, "tarfile: %s" % e)
609
610 def extract(self, member, path=""):
611 """Extract a member from the archive to the current working directory,
612 using its full name. Its file information is extracted as accurately
613 as possible. `member' may be a filename or a TarInfo object. You can
614 specify a different directory using `path'.
615 """
616 self._check("r")
617
618 if isinstance(member, basestring):
619 tarinfo = self.getmember(member)
620 else:
621 tarinfo = member
622
623 # Prepare the link target for makelink().
624 if tarinfo.islnk():
625 tarinfo._link_target = os.path.join(path, tarinfo.linkname)
626
627 try:
628 self._extract_member(tarinfo, os.path.join(path, tarinfo.name))
629 except EnvironmentError, e:
630 if self.errorlevel > 0:
631 raise
632 else:
633 if e.filename is None:
634 self._dbg(1, "tarfile: %s" % e.strerror)
635 else:
636 self._dbg(1, "tarfile: %s %r" % (e.strerror, e.filename))
637 except ExtractError, e:
638 if self.errorlevel > 1:
639 raise
640 else:
641 self._dbg(1, "tarfile: %s" % e)
642
643 def extractfile(self, member):
644 """Extract a member from the archive as a file object. `member' may be
645 a filename or a TarInfo object. If `member' is a regular file, a
646 file-like object is returned. If `member' is a link, a file-like
647 object is constructed from the link's target. If `member' is none of
648 the above, None is returned.
649 The file-like object is read-only and provides the following
650 methods: read(), readline(), readlines(), seek() and tell()
651 """
652 self._check("r")
653
654 if isinstance(member, basestring):
655 tarinfo = self.getmember(member)
656 else:
657 tarinfo = member
658
659 if tarinfo.isreg():
660 return self.fileobject(self, tarinfo)
661
662 elif tarinfo.type not in SUPPORTED_TYPES:
663 # If a member's type is unknown, it is treated as a
664 # regular file.
665 return self.fileobject(self, tarinfo)
666
667 elif tarinfo.islnk() or tarinfo.issym():
668 if isinstance(self.fileobj, _Stream):
669 # A small but ugly workaround for the case that someone tries
670 # to extract a (sym)link as a file-object from a non-seekable
671 # stream of tar blocks.
672 raise StreamError("cannot extract (sym)link as file object")
673 else:
674 # A (sym)link's file object is its target's file object.
675 return self.extractfile(self._find_link_target(tarinfo))
676 else:
677 # If there's no data associated with the member (directory, chrdev,
678 # blkdev, etc.), return None instead of a file object.
679 return None
680
681 def _extract_member(self, tarinfo, targetpath):
682 """Extract the TarInfo object tarinfo to a physical
683 file called targetpath.
684 """
685 # Fetch the TarInfo object for the given name
686 # and build the destination pathname, replacing
687 # forward slashes to platform specific separators.
688 targetpath = targetpath.rstrip("/")
689 targetpath = targetpath.replace("/", os.sep)
690
691 # Create all upper directories.
692 upperdirs = os.path.dirname(targetpath)
693 if upperdirs and not os.path.exists(upperdirs):
694 # Create directories that are not part of the archive with
695 # default permissions.
696 os.makedirs(upperdirs)
697
698 if tarinfo.islnk() or tarinfo.issym():
699 self._dbg(1, "%s -> %s" % (tarinfo.name, tarinfo.linkname))
700 else:
701 self._dbg(1, tarinfo.name)
702
703 if tarinfo.isreg():
704 self.makefile(tarinfo, targetpath)
705 elif tarinfo.isdir():
706 self.makedir(tarinfo, targetpath)
707 elif tarinfo.isfifo():
708 self.makefifo(tarinfo, targetpath)
709 elif tarinfo.ischr() or tarinfo.isblk():
710 self.makedev(tarinfo, targetpath)
711 elif tarinfo.islnk() or tarinfo.issym():
712 self.makelink(tarinfo, targetpath)
713 elif tarinfo.type not in SUPPORTED_TYPES:
714 self.makeunknown(tarinfo, targetpath)
715 else:
716 self.makefile(tarinfo, targetpath)
717
718 self.chown(tarinfo, targetpath)
719 if not tarinfo.issym():
720 self.chmod(tarinfo, targetpath)
721 self.utime(tarinfo, targetpath)
722
723 #--------------------------------------------------------------------------
724 # Below are the different file methods. They are called via
725 # _extract_member() when extract() is called. They can be replaced in a
726 # subclass to implement other functionality.
727
728 def makedir(self, tarinfo, targetpath):
729 """Make a directory called targetpath.
730 """
731 try:
732 # Use a safe mode for the directory, the real mode is set
733 # later in _extract_member().
734 os.mkdir(targetpath, 0700)
735 except EnvironmentError, e:
736 if e.errno != errno.EEXIST:
737 raise
738
739 def makefile(self, tarinfo, targetpath):
740 """Make a file called targetpath.
741 """
742 source = self.extractfile(tarinfo)
743 try:
744 with bltn_open(targetpath, "wb") as target:
745 copyfileobj(source, target)
746 finally:
747 source.close()
748
749 def makeunknown(self, tarinfo, targetpath):
750 """Make a file from a TarInfo object with an unknown type
751 at targetpath.
752 """
753 self.makefile(tarinfo, targetpath)
754 self._dbg(1, "tarfile: Unknown file type %r, " \
755 "extracted as regular file." % tarinfo.type)
756
757 def makefifo(self, tarinfo, targetpath):
758 """Make a fifo called targetpath.
759 """
760 if hasattr(os, "mkfifo"):
761 os.mkfifo(targetpath)
762 else:
763 raise ExtractError("fifo not supported by system")
764
765 def makedev(self, tarinfo, targetpath):
766 """Make a character or block device called targetpath.
767 """
768 if not hasattr(os, "mknod") or not hasattr(os, "makedev"):
769 raise ExtractError("special devices not supported by system")
770
771 mode = tarinfo.mode
772 if tarinfo.isblk():
773 mode |= stat.S_IFBLK
774 else:
775 mode |= stat.S_IFCHR
776
777 os.mknod(targetpath, mode,
778 os.makedev(tarinfo.devmajor, tarinfo.devminor))
779
780 def makelink(self, tarinfo, targetpath):
781 """Make a (symbolic) link called targetpath. If it cannot be created
782 (platform limitation), we try to make a copy of the referenced file
783 instead of a link.
784 """
785 if hasattr(os, "symlink") and hasattr(os, "link"):
786 # For systems that support symbolic and hard links.
787 if tarinfo.issym():
788 if os.path.lexists(targetpath):
789 os.unlink(targetpath)
790 os.symlink(tarinfo.linkname, targetpath)
791 else:
792 # See extract().
793 if os.path.exists(tarinfo._link_target):
794 if os.path.lexists(targetpath):
795 os.unlink(targetpath)
796 os.link(tarinfo._link_target, targetpath)
797 else:
798 self._extract_member(self._find_link_target(tarinfo), targetpath)
799 else:
800 try:
801 self._extract_member(self._find_link_target(tarinfo), targetpath)
802 except KeyError:
803 raise ExtractError("unable to resolve link inside archive")
804
805 def chown(self, tarinfo, targetpath):
806 """Set owner of targetpath according to tarinfo.
807 """
808 if pwd and hasattr(os, "geteuid") and os.geteuid() == 0:
809 # We have to be root to do so.
810 try:
811 g = grp.getgrnam(tarinfo.gname)[2]
812 except KeyError:
813 g = tarinfo.gid
814 try:
815 u = pwd.getpwnam(tarinfo.uname)[2]
816 except KeyError:
817 u = tarinfo.uid
818 try:
819 if tarinfo.issym() and hasattr(os, "lchown"):
820 os.lchown(targetpath, u, g)
821 else:
822 if sys.platform != "os2emx":
823 os.chown(targetpath, u, g)
824 except EnvironmentError, e:
825 raise ExtractError("could not change owner")
826
827 def chmod(self, tarinfo, targetpath):
828 """Set file permissions of targetpath according to tarinfo.
829 """
830 if hasattr(os, 'chmod'):
831 try:
832 os.chmod(targetpath, tarinfo.mode)
833 except EnvironmentError, e:
834 raise ExtractError("could not change mode")
835
836 def utime(self, tarinfo, targetpath):
837 """Set modification time of targetpath according to tarinfo.
838 """
839 if not hasattr(os, 'utime'):
840 return
841 try:
842 os.utime(targetpath, (tarinfo.mtime, tarinfo.mtime))
843 except EnvironmentError, e:
844 raise ExtractError("could not change modification time")
845
846 #--------------------------------------------------------------------------
847 def next(self):
848 """Return the next member of the archive as a TarInfo object, when
849 TarFile is opened for reading. Return None if there is no more
850 available.
851 """
852 self._check("ra")
853 if self.firstmember is not None:
854 m = self.firstmember
855 self.firstmember = None
856 return m
857
858 # Read the next block.
859 self.fileobj.seek(self.offset)
860 tarinfo = None
861 while True:
862 try:
863 tarinfo = self.tarinfo.fromtarfile(self)
864 except EOFHeaderError, e:
865 if self.ignore_zeros:
866 self._dbg(2, "0x%X: %s" % (self.offset, e))
867 self.offset += BLOCKSIZE
868 continue
869 except InvalidHeaderError, e:
870 if self.ignore_zeros:
871 self._dbg(2, "0x%X: %s" % (self.offset, e))
872 self.offset += BLOCKSIZE
873 continue
874 elif self.offset == 0:
875 raise ReadError(str(e))
876 except EmptyHeaderError:
877 if self.offset == 0:
878 raise ReadError("empty file")
879 except TruncatedHeaderError, e:
880 if self.offset == 0:
881 raise ReadError(str(e))
882 except SubsequentHeaderError, e:
883 raise ReadError(str(e))
884 break
885
886 if tarinfo is not None:
887 self.members.append(tarinfo)
888 else:
889 self._loaded = True
890
891 return tarinfo
892
893 #--------------------------------------------------------------------------
894 # Little helper methods:
895
896 def _getmember(self, name, tarinfo=None, normalize=False):
897 """Find an archive member by name from bottom to top.
898 If tarinfo is given, it is used as the starting point.
899 """
900 # Ensure that all members have been loaded.
901 members = self.getmembers()
902
903 # Limit the member search list up to tarinfo.
904 if tarinfo is not None:
905 members = members[:members.index(tarinfo)]
906
907 if normalize:
908 name = os.path.normpath(name)
909
910 for member in reversed(members):
911 if normalize:
912 member_name = os.path.normpath(member.name)
913 else:
914 member_name = member.name
915
916 if name == member_name:
917 return member
918
919 def _load(self):
920 """Read through the entire archive file and look for readable
921 members.
922 """
923 while True:
924 tarinfo = self.next()
925 if tarinfo is None:
926 break
927 self._loaded = True
928
929 def _check(self, mode=None):
930 """Check if TarFile is still open, and if the operation's mode
931 corresponds to TarFile's mode.
932 """
933 if self.closed:
934 raise IOError("%s is closed" % self.__class__.__name__)
935 if mode is not None and self.mode not in mode:
936 raise IOError("bad operation for mode %r" % self.mode)
937
938 def _find_link_target(self, tarinfo):
939 """Find the target member of a symlink or hardlink member in the
940 archive.
941 """
942 if tarinfo.issym():
943 # Always search the entire archive.
944 linkname = "/".join(filter(None, (os.path.dirname(tarinfo.name), tarinfo.linkname)))
945 limit = None
946 else:
947 # Search the archive before the link, because a hard link is
948 # just a reference to an already archived file.
949 linkname = tarinfo.linkname
950 limit = tarinfo
951
952 member = self._getmember(linkname, tarinfo=limit, normalize=True)
953 if member is None:
954 raise KeyError("linkname %r not found" % linkname)
955 return member
956
957 def __iter__(self):
958 """Provide an iterator object.
959 """
960 if self._loaded:
961 return iter(self.members)
962 else:
963 return TarIter(self)
964
965 def _dbg(self, level, msg):
966 """Write debugging output to sys.stderr.
967 """
968 if level <= self.debug:
969 print >> sys.stderr, msg
970
971 def __enter__(self):
972 self._check()
973 return self
974
975 def __exit__(self, type, value, traceback):
976 if type is None:
977 self.close()
978 else:
979 # An exception occurred. We must not call close() because
980 # it would try to write end-of-archive blocks and padding.
981 if not self._extfileobj:
982 self.fileobj.close()
983 self.closed = True
984 # class TarFile
985
986 TarFile
987
988 TarFile 源码
TarFile 源码
（6）json 和 pickle模块：文件只能存二进制或字符串，不能存其他类型，所以用到了用于序列化的两个模块
（7）shelve模块：shelve模块内部对pickle进行了封装，shelve模块是一个简单的k,v将内存数据通过文件持久化的模块，可以持久化任何pickle可支持的python数据格式 （可以存储数据、获取数据、给数据重新赋值）
#!/usr/bin/env python
# -*- coding:utf-8 -*-
#-Author-solo
import shelve
# k，v方式存储数据
s = shelve.open("shelve_test") # 打开一个文件
tuple = (1, 2, 3, 4)
list = ['a', 'b', 'c', 'd']
info = {"name": "lzl", "age": 18}
s["tuple"] = tuple # 持久化元组
s["list"] = list
s["info"] = info
s.close()
# 通过key获取value值
d = shelve.open("shelve_test") # 打开一个文件
print(d["tuple"]) # 读取
print(d.get("list"))
print(d.get("info"))
# (1, 2, 3, 4)
# ['a', 'b', 'c', 'd']
# {'name': 'lzl', 'age': 18}
d.close()
# 循环打印key值
s = shelve.open("shelve_test") # 打开一个文件
for k in s.keys(): # 循环key值
print(k)
# list
# tuple
# info
s.close()
# 更新key的value值
s = shelve.open("shelve_test") # 打开一个文件
s.update({"list":[22,33]}) #重新赋值或者s["list"] = [22,33]
print(s["list"])
#[22, 33]
s.close()
（8）xml模块：xml是实现不同语言或程序之间进行数据交换的协议，跟json差不多，但json使用起来更简单（通过<>节点来区别数据结构）
1 <?xml version="1.0"?><data> 2 <country name="Liechtenstein"> 3 <rank updated="yes">2</rank> 4 <year>2008</year> 5 <gdppc>141100</gdppc> 6 <neighbor name="Austria" direction="E"/> 7 <neighbor name="Switzerland" direction="W"/> 8 </country> 9 <country name="Singapore"> 10 <rank updated="yes">5</rank> 11 <year>2011</year> 12 <gdppc>59900</gdppc> 13 <neighbor name="Malaysia" direction="N"/> 14 </country> 15 <country name="Panama"> 16 <rank updated="yes">69</rank> 17 <year>2011</year> 18 <gdppc>13600</gdppc> 19 <neighbor name="Costa Rica" direction="W"/> 20 <neighbor name="Colombia" direction="E"/> 21 </country></data> 文件
1 import xml.etree.ElementTree as ET
2 tree = ET.parse("xmltest.xml")
3 root = tree.getroot()
4 print(root.tag)
5 #遍历xml文档
6 for child in root:
7 print(child.tag, child.attrib)
8 for i in child:
9 print(i.tag,i.text)
10 #只遍历year 节点
11 for node in root.iter('year'):
12 print(node.tag,node.text)
13 #修改
14 for node in root.iter('year'):
15 new_year = int(node.text) + 1
16 node.text = str(new_year)
17 node.set("updated","yes")
18 tree.write("xmltest.xml")
19 #删除node
20 for country in root.findall('country'):
21 rank = int(country.find('rank').text)
22 if rank > 50:
23 root.remove(country)
24 tree.write('output.xml')
25
26 ###########自己创建xml文档
27 import xml.etree.ElementTree as ET
28 new_xml = ET.Element("namelist")
29 name = ET.SubElement(new_xml,"name",attrib={"enrolled":"yes"})
30 age = ET.SubElement(name,"age",attrib={"checked":"no"})
31 sex = ET.SubElement(name,"sex")
32 sex.text = '33'
33 name2 = ET.SubElement(new_xml,"name",attrib={"enrolled":"no"})
34 age = ET.SubElement(name2,"age")
35 age.text = '19'
36 et = ET.ElementTree(new_xml) #生成文档对象
37 et.write("test.xml", encoding="utf-8",xml_declaration=True)
38 ET.dump(new_xml) #打印生成的格式
操作
（9）configparser模块：用于生成和修改配置文档（很少在程序中修改配置文件）
（10）hashlib模块：用于加密相关的操作，3.x里代替了md5模块和sha模块，主要提供 SHA1, SHA224, SHA256, SHA384, SHA512 ，MD5 算法
1 import hashlib
2 m = hashlib.md5()
3 m.update(b"Hello")
4 m.update(b"It's me")
5 print(m.digest())
6 m.update(b"It's been a long time since last time we ...")
7 print(m.digest()) #2进制格式hash
8 print(len(m.hexdigest())) #16进制格式hash
9 '''
10 def digest(self, *args, **kwargs): # real signature unknown
11 """ Return the digest value as a string of binary data. """
12 pass
13 def hexdigest(self, *args, **kwargs): # real signature unknown
14 """ Return the digest value as a string of hexadecimal digits. """
15 pass
16 '''
17 import hashlib
18 # ######## md5 ########
19 hash = hashlib.md5()
20 hash.update('admin')
21 print(hash.hexdigest())
22 # ######## sha1 ########
23 hash = hashlib.sha1()
24 hash.update('admin')
25 print(hash.hexdigest())
26 # ######## sha256 ########
27 hash = hashlib.sha256()
28 hash.update('admin')
29 print(hash.hexdigest())
30 # ######## sha384 ########
31 hash = hashlib.sha384()
32 hash.update('admin')
33 print(hash.hexdigest())
34 # ######## sha512 ########
35 hash = hashlib.sha512()
36 hash.update('admin')
37 print(hash.hexdigest())
hashlib
1 import hmac
2 h = hmac.new('wueiqi')
3 h.update('hellowo')
4 print h.hexdigest()
（11）re模块：用于对python的正则表达式的操作；匹配（动态模糊的匹配）；关键是匹配条件
1 '.' 默认匹配除\n之外的任意一个字符，若指定flag DOTALL,则匹配任意字符，包括换行
2 '^' 匹配字符开头，若指定flags MULTILINE,这种也可以匹配上(r"^a","\nabc\neee",flags=re.MULTILINE)
3 '$' 匹配字符结尾，或e.search("foo$","bfoo\nsdfsf",flags=re.MULTILINE).group()也可以
4 '*' 匹配*号前的字符0次或多次，re.findall("ab*","cabb3abcbbac") 结果为['abb', 'ab', 'a']
5 '+' 匹配前一个字符1次或多次，re.findall("ab+","ab+cd+abb+bba") 结果['ab', 'abb']
6 '?' 匹配前一个字符1次或0次
7 '{m}' 匹配前一个字符m次
8 '{n,m}' 匹配前一个字符n到m次，re.findall("ab{1,3}","abb abc abbcbbb") 结果'abb', 'ab', 'abb']
9 '|' 匹配|左或|右的字符，re.search("abc|ABC","ABCBabcCD").group() 结果'ABC'
10 '(...)' 分组匹配，re.search("(abc){2}a(123|456)c", "abcabca456c").group() 结果 abcabca456c
11 '[a-z]' 匹配a到z任意一个字符
12 '[^()]' 匹配除()以外的任意一个字符
13 '\A' 只从字符开头匹配，re.search("\Aabc","alexabc") 是匹配不到的
14 '\Z' 匹配字符结尾，同$
15 '\d' 匹配数字0-9
16 '\D' 匹配非数字
17 '\w' 匹配[A-Za-z0-9]
18 '\W' 匹配非[A-Za-z0-9]
19 '\s' 匹配空白字符、\t、\n、\r , re.search("\s+","ab\tc1\n3").group() 结果 '\t'
20 '(?P<name>...)' 分组匹配 re.search("(?P<province>[0-9]{4})(?P<city>[0-9]{2})(?P<birthday>[0-9]{4})","371481199306143242").groupdict("city")
21 结果{'province': '3714', 'city': '81', 'birthday': '1993'}
正则表达式
①、match：从起始位置开始去匹配
#match
import re
obj = re.match('\d+', '123uua123sf') #从第一个字符开始匹配一个到多个数字
print(obj)
#<_sre.SRE_Match object; span=(0, 3), match='123'>
if obj: #如果有匹配到字符则执行，为空不执行
print(obj.group()) #打印匹配到的内容
#123
②、search：最前面去匹配（不一定是最开始位置），匹配最前
#search
import re
obj = re.search('\d+', 'a123uu234asf') #从数字开始匹配一个到多个数字
print(obj)
#<_sre.SRE_Match object; span=(1, 4), match='123'>
if obj: #如果有匹配到字符则执行，为空不执行
print(obj.group()) #打印匹配到的内容
#123
import re
obj = re.search('\([^()]+\)', 'sdds(a1fwewe2(3uusfdsf2)34as)f') #匹配最里面（）的内容
print(obj)
#<_sre.SRE_Match object; span=(13, 24), match='(3uusfdsf2)'>
if obj: #如果有匹配到字符则执行，为空不执行
print(obj.group()) #打印匹配到的内容
#(3uusfdsf2)
③、group与groups的区别
#group与groups的区别
import re
a = "123abc456"
b = re.search("([0-9]*)([a-z]*)([0-9]*)", a)
print(b)
#<_sre.SRE_Match object; span=(0, 9), match='123abc456'>
print(b.group())
#123abc456
print(b.group(0))
#123abc456
print(b.group(1))
#123
print(b.group(2))
#abc
print(b.group(3))
#456
print(b.groups())
#('123', 'abc', '456')
④、findall上述两中方式均用于匹配单值，即：只能匹配字符串中的一个，如果想要匹配到字符串中所有符合条件的元素，则需要使用 findall；findall没有group 用法
#findall
import re
obj = re.findall('\d+', 'a123uu234asf') #匹配多个
if obj: #如果有匹配到字符则执行，为空不执行
print(obj) #生成的内容为列表
#['123', '234']
⑤、sub：用于替换匹配的字符串
#sub
import re
content = "123abc456"
new_content = re.sub('\d+', 'ABC', content)
print(new_content)
#ABCabcABC
⑥、split：根据指定匹配进行分组(分割)
#split
import re
content = "1 - 2 * ((60-30+1*(9-2*5/3+7/3*99/4*2998+10*568/14))-(-4*3)/(16-3*2) )"
new_content = re.split('\*', content) #用*进行分割，分割为列表
print(new_content)
#['1 - 2 ', ' ((60-30+1', '(9-2', '5/3+7/3', '99/4', '2998+10', '568/14))-(-4', '3)/(16-3', '2) )']
content = "'1 - 2 * ((60-30+1*(9-2*5/3+7/3*99/4*2998+10*568/14))-(-4*3)/(16-3*2) )'"
new_content = re.split('[\+\-\*\/]+', content)
# new_content = re.split('\*', content, 1)
print(new_content)
#["'1 ", ' 2 ', ' ((60', '30', '1', '(9', '2', '5', '3', '7', '3', '99', '4', '2998', '10', '568', '14))',
# '(', '4', '3)', '(16', '3', "2) )'"]
inpp = '1-2*((60-30 +(-40-5)*(9-2*5/3 + 7 /3*99/4*2998 +10 * 568/14 )) - (-4*3)/ (16-3*2))'
inpp = re.sub('\s*','',inpp) #把空白字符去掉
print(inpp)
new_content = re.split('\(([\+\-\*\/]?\d+[\+\-\*\/]?\d+){1}\)', inpp, 1)
print(new_content)
#['1-2*((60-30+', '-40-5', '*(9-2*5/3+7/3*99/4*2998+10*568/14))-(-4*3)/(16-3*2))']
（12）urllib模块：提供了一系列用于操作URL的功能（利用程序去执行各种HTTP请求。如果要模拟浏览器完成特定功能，需要把请求伪装成浏览器。伪装的方法是先监控浏览器发出的请求，再根据浏览器的请求头来伪装，User-Agent头就是用来标识浏览器的。）
#!/usr/bin/env python
# -*- coding:utf-8 -*-
#-Author-solo
import urllib.request
def getdata():
url = "http://www.baidu.com"
data = urllib.request.urlopen(url).read()
data = data.decode("utf-8")
print(data)
getdata()
###urlopen返回的类文件对象支持close、read、readline、和readlines方法
十二、面向对象
面向过程编程：通过代码的层层堆积来实现功能。不易迭代和维护。
函数式编程：将某功能代码封装到函数中，仅调用函数即可
面向对象编程：利用“类”和“对象”来创建各种模型来实现对真实世界的描述；使用面向对象编程的原因一方面是因为它可以使程序的维护和扩展变得更简单，并且可以大大提高程序开发效率 ，另外，基于面向对象的程序可以使它人更加容易理解你的代码逻辑，从而使团队开发变得更从容。
1 #经典类
2 class A():
3 def __init__(self):
4 print("A")
5 class B(A):
6 pass
7 class C(A):
8 def __init__(self):
9 print("C")
10 class D(B,C):
11 pass
12 obj = D()
13 #A
14 #新式类
15 class A(object):
16 def __init__(self):
17 print("A")
18 class B(A):
19 pass
20 class C(A):
21 def __init__(self):
22 print("C")
23 class D(B,C):
24 pass
25 obj = D()
26 #C
经典类、新式类
1 #属性方法
2 class Flight(object):
3 def __init__(self, name):
4 self.flight_name = name
5 def checking_status(self):
6 print("checking flight %s status " % self.flight_name)
7 return 1
8 @property
9 def flight_status(self):
10 status = self.checking_status()
11 if status == 0:
12 print("flight got canceled...")
13 elif status == 1:
14 print("flight is arrived...")
15 elif status == 2:
16 print("flight has departured already...")
17 else:
18 print("cannot confirm the flight status...,please check later")
19 @flight_status.setter # 修改 执行修改操作时触发
20 def flight_status(self, status):
21 status_dic = {
22 0: "canceled",
23 1:"arrived",
24 2: "departured"
25 }
26 print("\033[31;1mHas changed the flight status to \033[0m", status_dic.get(status))
27 @flight_status.deleter # 删除
28 def flight_status(self):
29 print("status got removed...")
30 f = Flight("CA980")
31 f.flight_status = 0 # 触发@flight_status.setter 只执行setter装饰的代码
32 del f.flight_status # 触发@flight_status.deleter 只执行deleter装饰的代码
33
34 #执行相应的操作，触发相应的装饰器，此时不会再触发原来的属性，只执行装饰器下面的代码，需要做相应的操作可在代码块里添加（修改，删除）；只是触发了而已，装饰器并没有做什么操作
航班查询
类的特殊成员方法：
① __doc__ 表示类的描述信息
#__doc__
class Foo:
""" 描述类信息，这是用于看片的神奇 """
def func(self):
pass
print(Foo.__doc__)
# 描述类信息，这是用于看片的神奇
② __module__ 和 __class__
__module__ 表示当前操作的对象在哪个模块
__class__ 表示当前操作的对象的类是什么
# __module__ 和 __class__
class Foo:
""" 描述类信息，这是用于看片的神奇 """
def func(self):
pass
A = Foo()
print(A.__module__)
print(A.__class__)
# __main__
# <class '__main__.Foo'>
③ __init__ 构造方法，通过类创建对象时，自动触发执行
④ __del__析构方法，当对象在内存中被释放时，自动触发执行
⑤ __call__ 对象后面加括号，触发执行
注：__init__的执行是由创建对象触发的，即：对象 = 类名() ；而对于 __call__ 方法的执行是由对象后加括号触发的，即：对象() 或者 类()()
# __call__
class Foo:
def __init__(self):
pass
def __call__(self, *args, **kwargs):
print('__call__')
obj = Foo() # 执行 __init__
obj() # 执行 __call__
#__call__
⑥ __dict__ 查看类或对象中的所有成员
class Province:
country = 'China'
def __init__(self, name, count):
self.name = name
self.count = count
def func(self, *args, **kwargs):
print('func')
# 获取类的成员，即：静态字段、方法、
print(Province.__dict__)
# 输出：{'__init__': <function Province.__init__ at 0x0054D588>, '__dict__': <attribute '__dict__' of 'Province' objects>,
# '__doc__': None, 'func': <function Province.func at 0x0054D4B0>, '__weakref__': <attribute '__weakref__' of 'Province' objects>,
# 'country': 'China', '__module__': '__main__'}
obj1 = Province('HeBei', 10000)
print(obj1.__dict__)
# 获取 对象obj1 的成员
# 输出：{'count': 10000, 'name': 'HeBei'}
⑦ __str__ 如果一个类中定义了__str__方法，那么在打印 对象 时，默认输出该方法的返回值
#__str__
class Foo:
def __str__(self):
return 'solo'
obj = Foo()
print(obj) #输出__str__返回值 而不是内存地址
# 输出：solo
⑧ __getitem__、__setitem__、__delitem__
用于索引操作，如字典。以上分别表示获取、设置、删除数据
#__getitem__、__setitem__、__delitem__
class Foo(object):
def __getitem__(self, key):
print('__getitem__', key)
def __setitem__(self, key, value):
print('__setitem__', key, value)
def __delitem__(self, key):
print('__delitem__', key)
obj = Foo()
result = obj['k1'] # 自动触发执行 __getitem__
obj['k2'] = 'solo' # 自动触发执行 __setitem__
del obj['k1']
# __getitem__ k1
# __setitem__ k2 solo
# __delitem__ k1
⑨ __new__ \ __metaclass__
1 print type(f) # 输出：<class '__main__.Foo'> 表示，obj 对象由Foo类创建 2 print type(Foo) # 输出：<type 'type'> 表示，Foo类对象由 type 类创建
f对象是Foo类的一个实例，Foo类对象是 type 类的一个实例，即：Foo类对象 是通过type类的构造方法创建
是由 type 类实例化产生那么问题来了，类默认是由 type 类实例化产生，type类中如何实现的创建类？类又是如何创建对象？
答：类中有一个属性 __metaclass__，其用来表示该类由 谁 来实例化创建，所以，我们可以为 __metaclass__ 设置一个type类的派生类，从而查看 类 创建的过程
class MyType(type):
def __init__(self, what, bases=None, dict=None):
print("--MyType init---")
super(MyType, self).__init__(what, bases, dict)
def __call__(self, *args, **kwargs):
print("--MyType call---")
obj = self.__new__(self, *args, **kwargs)
self.__init__(obj, *args, **kwargs)
class Foo(object):
__metaclass__ = MyType
def __init__(self, name):
self.name = name
print("Foo ---init__")
def __new__(cls, *args, **kwargs):
print("Foo --new--")
return object.__new__(cls)
# 第一阶段：解释器从上到下执行代码创建Foo类
# 第二阶段：通过Foo类创建obj对象
obj = Foo("solo")
反射：通过字符串映射或修改程序运行时的状态、属性、方法。 有以下4个方法
① hasattr(obj,str) 判断一个对象obj里是否有对应的str字符串的方法
② getattr(obj,str) 根据字符串去获取obj对象里的对应的方法的内存地址
class Foo(object):
def __init__(self,name):
self.name = name
def func(self):
print("func",self.name)
obj = Foo("alex")
str = "func"
print(hasattr(obj,str)) # 检查是否含有成员 有没有obj.str属性
if hasattr(obj,str):
getattr(obj,str)() #getattr(obj,str) = obj.str
# True
# func alex
③ setattr(obj,'y','z') obj.y = z 通过字符串添加属性
def bulk(self):
print("%s is yelling"%self.name)
class Foo(object):
def __init__(self,name):
self.name = name
def func(self):
print("func",self.name)
obj = Foo("alex")
str = "talk"
print(hasattr(obj,str)) # 检查是否含有成员 有没有obj.str属性
if hasattr(obj,str):
getattr(obj,str)() # getattr(obj,str) = obj.str
else:
setattr(obj,str,bulk) # setattr(obj,str,bulk 相当于 obj.str = bulk
getattr(obj,str)()
# False
# alex is yelling
④ delattr(obj,str) 删除obj.str 通过字符串删除属性
class Foo(object):
def __init__(self,name):
self.name = name
def func(self):
print("func",self.name)
obj = Foo("alex")
str = "name"
if hasattr(obj,str):
delattr(obj,str) # 删除属性obj.str
print(obj.name)
# Traceback (most recent call last):
# File "C:/Users/L/PycharmProjects/s14/preview/Day7/main.py", line 40, in <module>
# print(obj.name)
# AttributeError: 'Foo' object has no attribute 'name'
十三、Python垃圾回收机制
概述：和许多其它的高级语言一样，Python使用了垃圾回收器来自动销毁那些不再使用的对象。每个对象都有一个引用计数，当这个引用计数为0时Python能够安全地销毁这个对象
问题点：由于一次仅能有一个对象被回收，引用计数无法回收循环引用的对象。
解决方案：弱引用：减少循环引用，减少内存中不必要的对象存在的数量。对象可能在任何时刻被回收。
本文标题：Python语言基础
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