« 上一篇

使用轻量级ORM Dapper进行增删改查

 使用 Dapper 进行简单增删改查示例

首先根据数据库表定义实体对象, 这个工作完全可以使用T4、Nvelocity或者RazorEngine 写一个代码生成器根据数据库表对象自动生成数据库表实体对象。这里我自己根据表写了一个对象

[Table("UserRole")]
public class UserRoleDbEntity:DbEntityModelBase
{
	[Description("用户编号,来自用户表")]
	public int UserId
	{
		get;
		set;
	}

    [Description("角色编号,来自于角色表")]
	public int RoleId
	{
		get;
		set;
	}
	
	
	/// <summary>
	/// 备注:AuthorityEnum.AuthorityValue 的取值范围是根据 AuthorityEnum位运算 或 与 的结果集;不可随意赋值
	/// </summary>
	[Description("权限值")]
	public int AuthorityValue 
	{ 
		get; 
		set; 
	}


	/// <summary>
	/// 根据 AuthorityEnum 枚举值生成的描述
	/// </summary>
	[Description("权限描述")]
	public string AuthorityDescription 
	{ 
	  get; 
	  set; 
	}
}

    
/// <summary>
/// 所有DbEntityModel项目中的实体必须继承DbEntityModelBase或其子类,使用supperType模式控制共有子类的行为或者状态,此项目中的类根据数据库基本表或者视图保持基本一致
/// </summary>
public abstract class DbEntityModelBase
{
	[Description("Guid标识")]
	public string GuidMark
	{
		get;
		set;
	}
	
	[Description("自增Id列")]
	public int Id
	{
		get;
		set;
	}
	
   [Description("排序,倒序")]
	public int Sort
	{
		get;
		set;
	}
}

在DAL层就可以使用实体对象传参 或者作为返回值

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using OnlineExercise.DbAccess;
using Dapper;
using System.Configuration;
using System.Data;
using MySql.Data;
using MySql.Data.MySqlClient;
using OnlineExercise.DbEntityModel;
using OnlineExercise.Log;
using OnlineExercise.Infrastructrue;

namespace OnlineExercise.DbAccess.SysAdminModule
{
    public class UserRoleDB:DalBase<UserRoleDB>
    {
        public int AddUserRole(UserRoleDbEntity model)
        {
            int affecgtRow = 0;
            string sql = @"INSERT INTO  `userrole`
                                    (`GuidMark`,
                                     `UserId`,
                                     `RoleId`,
                                     `AuthorityValue`,
                                     `AuthorityDescription`)
                        VALUES (@GuidMark,
                                @UserId,
                                @RoleId,
                                @AuthorityValue,
                                @AuthorityDescription);";
            using (IDbConnection conn = new MySqlConnection(GlobalVariablesManager.G_Strconn))
            {
                affecgtRow = conn.Execute(sql, model);
            }
            return affecgtRow;
        }

        public int UpdateUserRoleByRoleIdAndUserId(UserRoleDbEntity model)
        {
            int affecgtRow = 0;
            string sql = @"UPDATE  `userrole`
                            SET  `AuthorityValue` = @AuthorityValue,
                                `AuthorityDescription` = @AuthorityDescription
                            WHERE `UserId` = @UserId
                                AND `RoleId` = @RoleId;";
            using (IDbConnection conn = new MySqlConnection(GlobalVariablesManager.G_Strconn))
            {
                affecgtRow = conn.Execute(sql, model);
            }
            return affecgtRow;
        }

        public int UpdateUserRoleByRoleId(UserRoleDbEntity model)
        {
            int affecgtRow = 0;
            string sql = @"UPDATE  `userrole`
                            SET  `AuthorityValue` = @AuthorityValue,
                                `AuthorityDescription` = @AuthorityDescription
                            WHERE `RoleId` = @RoleId;";
            using (IDbConnection conn = new MySqlConnection(GlobalVariablesManager.G_Strconn))
            {
                affecgtRow = conn.Execute(sql, model);
            }
            return affecgtRow;
        }

        public int UpdateUserRoleByUserId(UserRoleDbEntity model)
        {
            int affecgtRow = 0;
            string sql = @"UPDATE  `userrole`
                            SET  `AuthorityValue` = @AuthorityValue,
                                `AuthorityDescription` = @AuthorityDescription
                            WHERE `UserId` = @UserId;";
            using (IDbConnection conn = new MySqlConnection(GlobalVariablesManager.G_Strconn))
            {
                affecgtRow = conn.Execute(sql, model);
            }
            return affecgtRow;
        }

        public List<UserRoleDbEntity> GetUserRoleListByRoleId(UserRoleDbEntity model)
        {
            List<UserRoleDbEntity> modelList = null;
            string sql = @"SELECT
                              `Id`,
                              `GuidMark`,
                              `sort`,
                              `UserId`,
                              `RoleId`,
                              `AuthorityValue`,
                              `AuthorityDescription`
                            FROM `userrole`
                            WHERE RoleId=@RoleId;";
            using (IDbConnection conn = new MySqlConnection(GlobalVariablesManager.G_Strconn))
            {
                modelList = conn.Query<UserRoleDbEntity>(sql, model).ToList<UserRoleDbEntity>();
            }
            return modelList;
        }


        public List<UserRoleDbEntity> GetUserRoleListByUserId(string userId)
        {
            List<UserRoleDbEntity> modelList = null;
            string sql = @"SELECT
                              `Id`,
                              `GuidMark`,
                              `sort`,
                              `UserId`,
                              `RoleId`,
                              `AuthorityValue`,
                              `AuthorityDescription`
                            FROM `userrole`
                            WHERE UserId=@UserId;";
            using (IDbConnection conn = new MySqlConnection(GlobalVariablesManager.G_Strconn))
            {
                modelList = conn.Query<UserRoleDbEntity>(sql, new { UserId =userId}).ToList<UserRoleDbEntity>();
            }
            return modelList;
        }

        public List<UserRoleDbEntity> GetUserRoleListByRoleIdAndUserId(UserRoleDbEntity model)
        {
            List<UserRoleDbEntity> modelList = null;
            string sql = @"SELECT
                              `Id`,
                              `GuidMark`,
                              `sort`,
                              `UserId`,
                              `RoleId`,
                              `AuthorityValue`,
                              `AuthorityDescription`
                            FROM `userrole`
                            WHERE RoleId=@RoleId and UserId=@UserId;";
            using (IDbConnection conn = new MySqlConnection(GlobalVariablesManager.G_Strconn))
            {
                modelList = conn.Query<UserRoleDbEntity>(sql, model).ToList<UserRoleDbEntity>();
            }
            return modelList;
        }

        public int DeleteUserRoleByUserId(string userId)
        {
            int affecgtRow = 0;
            string sql = @"DELETE
                            FROM  `userrole`
                            WHERE `UserId` = @UserId";
            using (IDbConnection conn = new MySqlConnection(GlobalVariablesManager.G_Strconn))
            {
                affecgtRow = conn.Execute(sql, new { UserId = userId });
            }
            return affecgtRow;
        }

        public int DeleteUserRoleByRoleId(string roleId)
        {
            int affecgtRow = 0;
            string sql = @"DELETE
                            FROM  `userrole`
                            WHERE `RoleId` = @RoleId;";
            using (IDbConnection conn = new MySqlConnection(GlobalVariablesManager.G_Strconn))
            {
                affecgtRow = conn.Execute(sql, new { RoleId = roleId });

            }
            return affecgtRow;
        }

        public DataTable GetRoleInfoByUserId(string userId)
        {
            DataTable dt = null;

            string sql = @"SELECT b.*,a.userid,c.name as userName  FROM userrole AS a
                                INNER JOIN role AS b ON a.roleid=b.id
                                INNER JOIN USER AS c ON c.id=a.userid
                                WHERE a.userid=@userid;";
            using (IDbConnection conn = new MySqlConnection(GlobalVariablesManager.G_Strconn))
            {
                IDataReader reader = conn.ExecuteReader(sql, new { userid=userId });
                dt = CoreUtil.DataReader2Table(reader);
                reader.Dispose();
            }

            return dt;
        }

    }
}

 

Dapper的优势

 1、 Dapper是一个轻型的ORM类

 2、 Dapper语法简单,如果你喜欢写原始的sql,你一定喜欢Dapper。同时团队人员也很容易上手

 3、 Dapper 速度快,速度接近ADO.NET访问数据库的效率。

 4、 据库切换方便   


 public int UpdateUserRoleByRoleId(UserRoleDbEntity model)
 {
            int affecgtRow = 0;
            string sql = @"UPDATE  `userrole`
                            SET  `AuthorityValue` = @AuthorityValue,
                                `AuthorityDescription` = @AuthorityDescription
                            WHERE `RoleId` = @RoleId;";
            using (IDbConnection conn = new MySqlConnection(GlobalVariablesManager.G_Strconn))
            {
                affecgtRow = conn.Execute(sql, model);
            }
            return affecgtRow;
}

这里mysql如果要切换为Sql Server ,只要修改链接  MySqlConnection---》SqlConnection。


Dapper更多特性

动态dynamic绑定

var rows = connection.Query("select 1 A, 2 B union all select 3, 4");

((int)rows[0].A)
   .IsEqualTo(1);

((int)rows[0].B)
   .IsEqualTo(2);

((int)rows[1].A)
   .IsEqualTo(3);

((int)rows[1].B)
    .IsEqualTo(4);

批量插入

connection.Execute(@"insert MyTable(colA, colB) values (@a, @b)",    new[] { new { a=1, b=1 }, new { a=2, b=2 }, new { a=3, b=3 } }   )
          .IsEqualTo(3); 
// 3 rows inserted: "1,1", "2,2" and "3,3"

多表关联

var sql =
@"select * from #Posts p
left join #Users u on u.Id = p.OwnerId
Order by p.Id";

var data = connection.Query<Post, User, Post>(sql, (post, user) => { post.Owner = user; return post;});
var post = data.First();

post.Content.IsEqualTo("Sams Post1");
post.Id.IsEqualTo(1);
post.Owner.Name.IsEqualTo("Sam");
post.Owner.Id.IsEqualTo(99);

多结果查询

var sql =
@"
select * from Customers where CustomerId = @id
select * from Orders where CustomerId = @id
select * from Returns where CustomerId = @id";

using (var multi = connection.QueryMultiple(sql, new {id=selectedId}))
{
   var customer = multi.Read<Customer>().Single();
   var orders = multi.Read<Order>().ToList();
   var returns = multi.Read<Return>().ToList();
   ...
}

存储过程

var user = cnn.Query<User>("spGetUser", new {Id = 1},
        commandType: CommandType.StoredProcedure).SingleOrDefault();
// 你还可以获取存储过程out参数的输出值或者返回值
var p = new DynamicParameters();
p.Add("@a", 11);
p.Add("@b", dbType: DbType.Int32, direction: ParameterDirection.Output);
p.Add("@c", dbType: DbType.Int32, direction: ParameterDirection.ReturnValue);

cnn.Execute("spMagicProc", p, commandType: CommandType.StoredProcedure);

int b = p.Get<int>("@b");
int c = p.Get<int>("@c");

参数自动绑定

new {A = 1, B = "b"} // A will be mapped to the param @A, B to the param @B