Dapper进行增删改查 z

http://www.cnblogs.com/huangkaiyan10/p/4640548.html

项目背景

     前一段时间，开始做一个项目，在考虑数据访问层是考虑技术选型，考虑过原始的ADO.NET、微软的EF、NH等。再跟经理讨论后，经理强调不要用 Ef，NH做ORM，后期的sql优化不好做，公司也没有人对EF，Nh 等orm优化比较熟悉的。强调说的，我们的项目要做的得简单，可以使用ADO.NET 写原始的sql。但我自己还是喜欢ORM的，它可以提高数据访问层的开发。有一天，在订阅张善友 doNet跨平台微信公众号里，看到Dapper的推荐。了解之后，我自己喜欢喜欢Dapper，可以满足我这个项目的经理的要求，同时Dapper 对数据库的访问能做到Ado.net一样快。

  下面的链接是Dapper 在github的地址  https://github.com/StackExchange/dapper-dot-net。

  使用 Dapper 进行简单增删改查示例

   1、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;
        }
    }

  2. 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、多数据库切换方便

    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

1、支持动态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);

2、支持批量插入

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

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