Dapper-開源小型ORM

 一些關於Dapper的介紹：

 1.Dapper是一個輕型的開源ORM類，代碼就一個SqlMapper.cs文件，編譯後就40多K的一個很小的Dll. 

 2.Dapper支持Mysql,SqlLite,Mssql2000,Mssql2005,Oracle等一系列的數據庫

 3.Dapper的r支持多表並聯的對象。支持一對多 多對多的關係。而且沒侵入性。

 4.Dapper原理經過Emit反射IDataReader的序列隊列，來快速的獲得和產生對象。性能提高了不少；（比採用常規的反射）而且無須遷就數據庫的設計。

 Dapper源碼下載連接：

 點擊這裏下載dapper源代碼。

 Demo:

           var connection = GetOpenConnection();

            var guid = Guid.NewGuid();
            string id = "6e2a106d-d838-48b9-ac74-ad604457bba2";

            //1泛型
            var dog = connection.Query<Dog>("select * from Dog where Id = @Id", new { Id = id });
            
            //2 動態解析
            var rows = connection.Query("select * from Dog where Id = @Id", new { Id = id }).ToList();
            foreach (dynamic item in rows)
            {
                 String 黑客 = item.Name;
            }

Query

 

            //3.執行不返回結果
            int result=connection.Execute("insert into Dog values(@age,@id,@name,@weight,@ignoredproperty)", new { age = 49, id = Guid.NewGuid(), name = "YZR", weight = 117.5, ignoredproperty = 1 });

Execute

            //4.批量Execute
            List<Dog> list = new List<Dog>();
            list.Add(new Dog() { Age = 9, Id = Guid.NewGuid(), Name = "ZXX", Weight = 120 });
            list.Add(new Dog() { Age = 9, Id = Guid.NewGuid(), Name = "WMJ", Weight = 120 });
            List<dynamic> paramsList = new List<dynamic>();
            foreach (Dog item in list)
            {
                paramsList.Add(new { age = item.Age, id = item.Id, name = item.Name, weight = item.Weight, ignoredproperty = 1 });
            }
            int result = connection.Execute("insert into Dog values(@age,@id,@name,@weight,@ignoredproperty)", paramsList);

批量Execute

            //5.In操做
            dog = connection.Query<Dog>("select * from Dog where id in @ids", new { ids = new String[] { "6e2a106d-d838-48b9-ac74-ad604457bba3", "6e2a106d-d838-48b9-ac74-ad604457bba2", "535dab3a-d3c1-4cb0-b8f7-63351f491056" } });
            //等價於
            dog = connection.Query<Dog>("select * from Dog where id in (@id1,@id2,@id3)", new { id1 = "6e2a106d-d838-48b9-ac74-ad604457bba3", id2 = "6e2a106d-d838-48b9-ac74-ad604457bba2", id3 = "535dab3a-d3c1-4cb0-b8f7-63351f491056" });

In操做

            //數據庫要創建主外鍵關係
            var sql =
                      @"select p.*,u.* from Dog p 
                                    left join Owner u on u.OwnerId = p.Id 
                                     where p.id=@id Order by p.Id";
            Dog d = null;
            var t = connection.Query(sql, new { id = "6e2a106d-d838-48b9-ac74-ad604457bba2" });
            var data = connection.Query<Dog, Owner, Dog>(sql, (post, user) =>
            {
                if (d == null || d.Id != post.Id)
                {
                    d = post;
                }
                if (user != null)
                {
                    d.user.Add(user);
                }
                return post;
            }, new { id = "6e2a106d-d838-48b9-ac74-ad604457bba2" });

一對多關係

            //多查詢的結果集
            sql =
                 @"select * from Dog where Id = @id
                   select * from Owner";

            using (var multi = connection.QueryMultiple(sql, new { id = "6e2a106d-d838-48b9-ac74-ad604457bba3" }))
            {

                 var data = multi.Read<Dog>().ToList();
                 var owner = multi.Read<Owner>().ToList();
             }

QueryMultiple

            //事務

            using (connection)
            {
                //開始事務
                IDbTransaction transaction = connection.BeginTransaction();
                try
                {
                    string query = "update Dog set Age=Age+1 where Id=@Id";
                    string query2 = "update Dog set Weight=Weight+1.0 where Id=@Id";
                    connection.Execute(query, new { Id = "71fff309-c7c9-4f64-b588-0a03e27459ba" }, transaction, null, null);
                    connection.Execute(query2, new { Id = "71fff309-c7c9-4f64-b588-0a03e27459ba" }, transaction, null, null);
                    //提交事務
                    transaction.Commit();
                }
                catch (Exception ex)
                {
                    //出現異常，事務Rollback
                    transaction.Rollback();
                    throw new Exception(ex.Message);
                }
            }

IDbTransaction

            //存儲過程

            var p = new DynamicParameters();
            //實例1
            //p.Add("@result", dbType: DbType.Int32, direction: ParameterDirection.Output);
            //var user = connection.Query("Test", p, commandType: CommandType.StoredProcedure);
            //int totalCount = p.Get<int>("@result");

            //實例2
            //注意點：調用若是使用query，那麼存儲過程須要有select結果集
            //p.Add("@result", dbType: DbType.Int32, direction: ParameterDirection.Output);
            //p.Add("@rowcount", dbType: DbType.Int32, direction: ParameterDirection.ReturnValue);
            //var user = connection.Query("TestValue", p, commandType: CommandType.StoredProcedure);
            //int re = p.Get<int>("@result");
            //int ro = p.Get<int>("@rowcount");

            //實例3
            //存儲過程分頁須要row_number() over( order by id)這個排序的id須要指定
            p.Add("@PageIndex", 1, dbType: DbType.Int32, direction: ParameterDirection.Input);
            p.Add("@PageSize", 3, dbType: DbType.Int32, direction: ParameterDirection.Input);
            p.Add("@TableName", "Dog", dbType: DbType.String, direction: ParameterDirection.Input);
            p.Add("@Where", " 1=1 order by id asc ", dbType: DbType.String, direction: ParameterDirection.Input);
            //p.Add("@rowcount", dbType: DbType.Int32, direction: ParameterDirection.Output);
            p.Add("@rowcount", dbType: DbType.Int32, direction: ParameterDirection.ReturnValue);
            var result = connection.Query("SelectBase", p, commandType: CommandType.StoredProcedure);

            int count = p.Get<int>("@rowcount");

Procedure

            //切換數據庫
            connection.ChangeDatabase("數據庫名稱");

ChangeDatabase

 

Demo源代碼下載

點擊這裏下載