c# .net orm 框架 dapper.net 的应用
之前用过 entity framework 5.0 、sqlhelper 、mybatis.net 等 orm，当然 sqlhelper 不算。
感觉都是学习陈本挺高的，配置也比较复杂，尤其是 mybatis 全是 xml ，懵逼了 ~~~~~
ef 用着不错也挺灵活，就是有些数据库不支持 如mysql，网上也找过ef 接入 mysql 的方法，觉得还是比较繁重
mybatis 支持大多数的数据库，实体映射也相对方便，就是灵活性太差，加一个表需要配置 好几个 xml
继续寻找及灵活又有实体映射的 orm，最后选择了 dapper.net。用过之后你也会喜欢上它的，有以下几个特性
1.类似 ado.net 的写法，灵活拼接sql
2.有实体和数据集的映射（支持一对一、一对多实体映射）
3.学习成本超级低只有两个方法 query（）、execute（）
4.可以说是 0 配置，只要在 config 中配置连接字符串就 ok了
5.类库非常小 只有一个 sqlMapper.cs 的文件（还是喜欢vs2015以前的代码，所以我用的是 dapper.net 1.4.2，上传到我的资源中）
上代码，里面包含增、删、改、查，和事务的使用（这里测试用的是mysql数据库）
一、数据脚本
#订单表
CREATE TABLE `order_info` (
`order_id` int(11) NOT NULL AUTO_INCREMENT COMMENT '订单id',
`user_id` int(11) DEFAULT NULL COMMENT '用户id',
`order_code` char(50) DEFAULT NULL COMMENT '订单号',
`amount` decimal(10,0) DEFAULT NULL COMMENT '订单金额',
`create_time` timestamp(6) NULL DEFAULT NULL COMMENT '下单时间',
`goods_count` int(11) DEFAULT NULL COMMENT '商品数量',
PRIMARY KEY (`order_id`)
) ENGINE=InnoDB AUTO_INCREMENT=6 DEFAULT CHARSET=utf8
#订单商品表
CREATE TABLE `order_item` (
`item_id` int(11) NOT NULL AUTO_INCREMENT COMMENT '订单内容id',
`order_id` int(11) NOT NULL COMMENT '商品id',
`goods_name` char(150) DEFAULT NULL COMMENT '商品名',
`unit_price` decimal(11,0) DEFAULT NULL COMMENT '单价',
`goods_count` int(11) DEFAULT NULL COMMENT '商品数量',
`amount` decimal(11,0) DEFAULT NULL COMMENT '总金额',
`create_time` timestamp(6) NULL DEFAULT NULL COMMENT '创建时间',
`update_time` timestamp(6) NULL DEFAULT NULL COMMENT '修改时间',
PRIMARY KEY (`item_id`)
) ENGINE=InnoDB AUTO_INCREMENT=8 DEFAULT CHARSET=utf8
#用户表
CREATE TABLE `user_info` (
`user_id` int(11) NOT NULL AUTO_INCREMENT COMMENT '用户id',
`user_name` char(50) DEFAULT NULL COMMENT '用户名',
`upwd` char(50) DEFAULT NULL COMMENT '密码',
`create_time` timestamp(6) NULL DEFAULT NULL COMMENT '创建时间',
`update_time` timestamp(6) NULL DEFAULT NULL COMMENT '修改时间',
`age` int(3) DEFAULT NULL COMMENT '年龄',
`sex` char(2) DEFAULT NULL COMMENT '性别',
PRIMARY KEY (`user_id`)
) ENGINE=InnoDB AUTO_INCREMENT=5 DEFAULT CHARSET=utf8
测试用的存储过程
#带有输入输出参数的过程
DELIMITER $$
CREATE PROCEDURE `p_getUserCount`(
_sex CHAR,
OUT _total INT)
BEGIN
SET @sex = _sex;
SELECT COUNT(*) INTO _total FROM user_info WHERE sex=@sex;
END$$
#返回数据集的过程
DELIMITER ;
CREATE DEFINER=`root`@`localhost` PROCEDURE `p_getUserInfo`(
_userid INT
)
BEGIN
SET @uid = _userid;
SET @sql = CONCAT('select * from user_info where user_id=',@uid );
IF(@uid<=0) THEN
SET @sql = 'select * from user_info';
END IF;
PREPARE strsql FROM @sql;#定义预处理语句
EXECUTE strsql;
DEALLOCATE PREPARE strsql; #删除定义
END$$
DELIMITER ;二、实体&工具类
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace TestDapperDotNet.Models
{
public class order_infoModel
{
public order_infoModel()
{
goodsList = new List();
}
public int order_id { set; get; }
public int user_id { set; get; }
public string order_code { set; get; }
public decimal amount { set; get; }
public DateTime create_time { set; get; }
public int goods_count { set; get; }
///
/// 下单用户信息(测试一对一映射)
///
public user_infoModel userInfo { set; get; }
///
/// 订单商品信息(测试一对多映射)
///
public List goodsList { set; get; }
}
public class order_itemModel
{
public int item_id { set; get; }
public int order_id { set; get; }
public string goods_name { set; get; }
public decimal unit_price { set; get; }
public int goods_count { set; get; }
public decimal amount { set; get; }
public DateTime create_time { set; get; }
public DateTime update_time { set; get; }
}
public class user_infoModel
{
public int user_id { set; get; }
public string user_name { set; get; }
public string upwd { set; get; }
public DateTime create_time { set; get; }
public DateTime update_time { set; get; }
public int age { set; get; }
public string sex { set; get; }
}
}
using System;
using System.Collections.Generic;
using System.Configuration;
using System.Linq;
using System.Text;
namespace TestDapperDotNet
{
public class DbConfig
{
public static readonly string Test_W =
ConfigurationManager.ConnectionStrings["test_w"].ConnectionString;
public static readonly string Test_R =
ConfigurationManager.ConnectionStrings["test_r"].ConnectionString;
}
} 三、dapper.net 测试类
using System;
using System.Collections.Generic;
using System.Data;
using System.Linq;
using Dapper;
using Microsoft.VisualStudio.TestTools.UnitTesting;
using TestDapperDotNet.Models;
namespace TestDapperDotNet
{
[TestClass]
public class TestDapper
{
///
/// 获取连接字符串
///
///
/// 查询记录返回实体
///
[TestMethod]
public void TestQueryT()
{
using (var conn = GetSqlConnection())
{
//订单表映射单条记录
var sql = @"SELECT * FROM order_info WHERE order_id=@order_id;";
var list = conn.Query(sql, new
{
order_id = 2
}).ToList();
var itme = list.FirstOrDefault();
Assert.IsTrue(itme.order_id == 2);
//订单表映射多条记录
sql = @"SELECT * FROM order_info";
list = conn.Query(sql, new
{
order_id = 2
}).ToList();
Assert.IsTrue(list != null && list.Count>0);
}
}
///
/// 一对一映射
/// 订单实体下有个用户信息属性，通过user_id关联
///
[TestMethod]
public void TestOneToOne()
{
using (IDbConnection conn = GetSqlConnection())
{
var sql = @"
SELECT a.*,b.*
FROM
order_info a
JOIN user_info b
ON a.`user_id`=b.user_id;";
var list = conn.Query(
sql
, (order, user) =>
{
order.userInfo = user;
return order;
}
, null
, null
, true
, "order_id"
, null
, null).ToList();
list.ForEach(x =>
{
Assert.IsTrue(x.userInfo.user_id == x.user_id);
});
Assert.IsTrue(true);
}
}
///
/// 一对多映射
///
[TestMethod]
public void TestOneToMore()
{
using (IDbConnection conn = GetSqlConnection())
{
var sql = @"
SELECT a.*,b.*
FROM
order_info a
JOIN order_item b
ON a.order_id=b.order_id;";
//合并后的订单数据
var orderDic = new Dictionary();
var originList = conn.Query(
sql
, (order, goods) =>
{
//需要手动维护，一对多对象关系
order_infoModel ord;
if (!orderDic.TryGetValue(order.order_id, out ord))
{
ord = order;
orderDic.Add(order.order_id, order);
}
ord.goodsList.Add(goods);
return order;
}
, null
, null
, true
, "order_id"
, null
, null).ToList();
//投影一个list
var list = orderDic.Select(x => x.Value).ToList();
list.ForEach(x =>
{
x.goodsList.ForEach(o =>
{
Assert.IsTrue(o.order_id == x.order_id);
});
});
Assert.IsTrue(true);
}
}
[TestMethod]
public void TestInsertOne()
{
var user = new user_infoModel()
{
user_name="tester",
upwd="123",
create_time=DateTime.Now,
update_time=DateTime.Now,
age=99,
sex="女"
};
var sql = @"
INSERT INTO `test`.`user_info` (
`user_id`,
`user_name`,
`upwd`,
`create_time`,
`update_time`,
`age`,
`sex`
)
VALUES
(
@user_id,
@user_name,
@upwd,
@create_time,
@update_time,
@age,
@sex
) ;";
using (IDbConnection conn = GetSqlConnection())
{
var n = conn.Execute(sql, user);
Assert.IsTrue(n == 1);
}
}
///
/// 执行"返回数据集"的存储过程
///
[TestMethod]
public void TestCallp_getuserinfo()
{
#region mysql 存储过程脚本
/*
DELIMITER $$
CREATE
PROCEDURE `test`.`p_getUserInfo`(
_userid INT
)
BEGIN
SET @uid = _userid;
SET @sql = CONCAT('select * from user_info where user_id=',@uid );
IF(@uid<=0) THEN
SET @sql = 'select * from user_info';
END IF;
PREPARE strsql FROM @sql;#定义预处理语句
EXECUTE strsql;
DEALLOCATE PREPARE strsql; #删除定义
END$$
DELIMITER ;
*/
#endregion
var sql = "p_getuserinfo";
using (IDbConnection conn = GetSqlConnection())
{
var list = conn.Query(sql,
new
{
_userid = 0 //查询多个
},
null,
true,
null,
CommandType.StoredProcedure).ToList();
Assert.IsTrue(list!=null);
}
}
///
/// 执行“带有输入输出参数”的存储过程
///
[TestMethod]
public void TestCallp_getUserCount()
{
#region mysql 存储过程脚本
/*
DELIMITER $$
CREATE PROCEDURE `p_getUserCount`(
_sex CHAR,
OUT _total INT)
BEGIN
SET @sex = _sex;
SELECT COUNT(*) INTO _total FROM user_info WHERE sex=@sex;
END$$
DELIMITER ;
*/
#endregion
var sql = "p_getUserCount";
DynamicParameters pars = new DynamicParameters();
pars.Add("_sex", "女");
pars.Add("_total", "", DbType.Int32, ParameterDirection.Output);
using (IDbConnection conn = GetSqlConnection())
{
var n = conn.Execute(sql,
pars,
null,
null,
CommandType.StoredProcedure);
var total = pars.Get("_total");
Assert.IsTrue(total > 0);
}
}
[TestMethod]
public void TestTransaction()
{
using (IDbConnection conn = GetSqlConnection())
{
conn.Open();
//开始事务
var transaction = conn.BeginTransaction();
try
{
var order = new order_infoModel()
{
amount = 100,
create_time = DateTime.Now,
goods_count = 3,
order_code = "20160608001",
user_id = 2,
};
var item = new order_itemModel()
{
amount = 100,
create_time = DateTime.Now,
goods_count = 3,
goods_name = "001",
order_id = 2,
unit_price = 99.99M,
update_time = DateTime.Now
};
var sql = @"
INSERT INTO `order_info` (
`user_id`,
`order_code`,
`amount`,
`create_time`,
`goods_count`
)
VALUES
(
@user_id,
@order_code,
@amount,
@create_time,
@goods_count
) ;";
int n = conn.Execute(sql, order, transaction);
Assert.IsTrue(n == 1);
if (n != 1)
{
transaction.Rollback();
return;
}
sql = @"
INSERT INTO `order_item` (
`order_id`,
`goods_name`,
`unit_price`,
`goods_count`,
`amount`,
`create_time`,
`update_time`
)
VALUES
(
@order_id,
@goods_name,
@unit_price,
@goods_count,
@amount,
@create_time,
@update_time
) ;";
n = conn.Execute(sql, item, transaction);
Assert.IsTrue(n == 1);
if (n != 1)
{
transaction.Rollback();
return;
}
//提交事务
transaction.Commit();
}
catch (Exception ex)
{
//出现异常，事务Rollback
transaction.Rollback();
}
}
}
}
}