类别:控件工具
日期:2020-09-27 浏览:2171 评论:0
easy4net是一个轻量级orm框架,灵活在于可以自己编写复杂的SQL语句查询,简单在于几分钟内便能上手使用,并支持mysql, mssql, oracle, access, sqlite数据库. easy4net技术QQ 群:162695864
分页查询:
命名参数, ParamMap传参方式:
支持多层嵌套查询自动分页功能。
int pageIndex = 1;
int pageSize = 3;
string strSql = "SELECT e.*, c.company_name FROM employee e INNER JOIN company c ON e.company_id = c.id WHERE e.name = @name";
ParamMap param = ParamMap.newMap();
param.setPageParamters(page, limit);
//分页时使用的排序字段,必填,请带上SQL表名的别名,如employee的为:
eparam.setOrderFields("e.id", true);param.setParameter("name", "LiYang");
//MySQLString是app.config或web.config中配置的连接数据库字符串,
//应部分用户需要可以切换多个数据库要求
Session session = SessionFactory.GetSession("MySQLString");
List<Employee> emList = session.Find<Employee>(strSql, param);
分页查询:
命名参数, ParamMap传参方式:
返回总条数和数据集合的对象PageResult
public PageResult<Store> findByPage(int page, int limit){
Session session = SessionFactory.GetSession("MySQLString");
String sql = "select * from store";
ParamMap param = ParamMap.newMap();
param.setPageParamters(page, limit);
param.setOrderFields("id", true);
PageResult<Store> pageResult = session.FindPage<Store>(sql, param);
return pageResult;}
public class PageResult<T>{
/// <summary>
/// 分页查询中总记录数
/// </summary>
public int Total {get; set;}
/// <summary>
/// 分页查询中结果集合
/// </summary>
public List<T> DataList {get; set;}
}
查询单条记录:
string strSql = "SELECT e.*, c.company_name FROM employee e INNER JOIN company c ON e.company_id = c.id WHERE e.name = @name";
ParamMap param = ParamMap.newMap();param.setParameter("name", "LiYang");
Employee em = session.Get<Employee>(strSql, param);
普通查询:
string strSql = "SELECT e.*, c.company_name FROM employee e INNER JOIN company c ON e.company_id = c.id";
List<Employee> emList = session.Find<Employee>(strSql);
新增:
新增后返回新增记录的主键id值
主键id值已经自动填充到新增的对象entity中
//创建公司
Company company = new Company();
company.CompanyName = txtName.Text.Trim();
company.Industry = txtIndustry.Text.Trim();
company.Address = txtAddress.Text.Trim();
Session session = SessionFactory.GetSession("MySQLString");
session.Insert<Company>(company);
if (company.Id > 0) {
MessageBox.Show("创建公司成功!");
}
//新增员工
Company company = m_CompanyList[cbCompany.SelectedIndex];
Employee employee = new Employee();
employee.Name = txtName.Text.Trim();
mployee.Age = Convert.ToInt32(txtAge.Text.Trim());
employee.Address = txtAddress.Text.Trim();
employee.Created = DateTime.Now;
employee.CompanyId = company.Id;
Session session = SessionFactory.GetSession("MySQLString");
session.Insert<Employee>(employee);
if (employee.Id > 0){
MessageBox.Show("新增员工成功!");
}
批量新增:
主键id值已经自动填充到新增的对象entity中
批量新增方法比手动循环多个对象然后调用新增性能高。
List<Company> companyList = ...;
Session session = SessionFactory.GetSession("MySQLString");session.Insert(companyList);
修改:
Company entity = new Company();entity.Id = 1;entity.Name = "百度";
Session session = SessionFactory.GetSession("MySQLString");session.Update(entity);
批量修改:
批量修改方法比手动循环多个对象然后调用修改性能高。
Session session = SessionFactory.GetSession("MySQLString");
List<Company> companyList = ...;
Session session = SessionFactory.GetSession("MySQLString");session.Update(companyList);
删除:
按对象方式删除数据
按主键id方式删除数据
Company company = m_companyList[i];
//remove a objectSession session = SessionFactory.GetSession("MySQLString");
session.Delete(company);//remove by idsession.Delete(company.Id);
批量删除:
按对象方式删除数据
按主键id方式删除数据
批量删除比手动循环调用删除性能要高
//remove by objectList<Company> companyList = ...;
Session session = SessionFactory.GetSession("MySQLString");
session.Delete(companyList);//remove by idobject[] ids = new object[]{1,2,3,4,5};
session.Delete(ids);
数据库与C#对象映射关系配置:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace Easy4net.Entity {
[Table(Name = "company")]
public class Company {
[Id(Name = "id", Strategy = GenerationType.INDENTITY)]
public int? Id{ get; set; }
[Column(Name = "company_name")]
public String CompanyName{ get; set; }
[Column(Name = "industry")]
public String Industry { get; set; }
[Column(Name = "address")]
public String Address { get; set; }
}
}
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Text;
namespace Easy4net.Entity {
[Table(Name = "employee")]
public class Employee
{
[Id(Name = "id", Strategy = GenerationType.INDENTITY)]
public int? Id{ get; set; }
[Column(Name = "name")]
public String Name{ get; set; }
[Column(Name = "age")]
public int? Age{ get; set; }
[Column(Name = "address")]
public String Address{ get; set; }
[Column(Name = "created")]
public DateTime? Created{ get; set; }
[Column(Name = "company_id")]
public int? CompanyId{ get; set; }
[Column(Name = "company_name", IsInsert = false, IsUpdate = false)]
public String CompanyName { get; set; }
}
}
数据库连接配置 web.config中:
dbType中配置sqlserver, mysql, oracle来支持不同的数据库
<?xml version="1.0"?>
<configuration>
<connectionStrings>
<add name="MySQLString" connectionString="Data Source=localhost;Initial Catalog=test_db;Persist Security Info=True;User ID=root;Password=123456;Min Pool Size=1;Max Pool Size=3;" providerName="MySql.Data.MySqlClient" />
<add name="SqlServerString" connectionString="Data Source=(local);Initial Catalog=Study;User ID=sa;Password=sa;" providerName="System.Data.SqlClient" />
<add name="OracleString" connectionString="Data Source=192.168.0.2;Initial Catalog=test;Persist Security Info=True;User ID=user1;Password=pass1" providerName="System.Data.OracleClient" />
<add name="SQLiteString" connectionString="Data Source=|DataDirectory|\testdb.sqlite;Pooling=true;" providerName="System.Data.SQLite" />
</connectionStrings>
<startup>
<supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.0"/>
</startup>
</configuration>
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