0.0 今天我又来了
问题解决与不解决他总是在那里.
1. 调整一下我的表结构,然后然后做一个one to manny 的查询
1 public class Order 2 { 3 public Guid OrderId { get; set; } 4 public string OrderCode { get; set; } 5 public string Address { get; set; } 6 public string UserName { get; set; } 7 public decimal TotalPrice { get; set; } 8 } 9 10 public class OrderDetail 11 { 12 public Guid OrderDetailId { get; set; } 13 public string ProductName { get; set; } 14 public string Count { get; set; } 15 public decimal Prcie { get; set; } 16 }
2.数据库的结构
1 USE [Demo] 2 GO 3 /****** Object: Table [dbo].[Order] Script Date: 2019/11/27 22:47:26 ******/ 4 SET ANSI_NULLS ON 5 GO 6 SET QUOTED_IDENTIFIER ON 7 GO 8 CREATE TABLE [dbo].[Order]( 9 [OrderId] [uniqueidentifier] NOT NULL, 10 [OrderCode] [nvarchar](50) NULL, 11 [Address] [nvarchar](100) NULL, 12 [UserName] [nvarchar](50) NULL, 13 [TotalPrice] [decimal](18, 2) NULL, 14 CONSTRAINT [PK_Order] PRIMARY KEY CLUSTERED 15 ( 16 [OrderId] ASC 17 )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] 18 ) ON [PRIMARY] 19 GO 20 /****** Object: Table [dbo].[OrderDetail] Script Date: 2019/11/27 22:47:26 ******/ 21 SET ANSI_NULLS ON 22 GO 23 SET QUOTED_IDENTIFIER ON 24 GO 25 CREATE TABLE [dbo].[OrderDetail]( 26 [OrderDetailId] [uniqueidentifier] NOT NULL, 27 [OrderId] [uniqueidentifier] NULL, 28 [ProductName] [nvarchar](100) NULL, 29 [Count] [int] NULL, 30 [Prcie] [decimal](18, 2) NULL, 31 CONSTRAINT [PK_OrderDetail] PRIMARY KEY CLUSTERED 32 ( 33 [OrderDetailId] ASC 34 )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] 35 ) ON [PRIMARY] 36 GO 37 INSERT [dbo].[Order] ([OrderId], [OrderCode], [Address], [UserName], [TotalPrice]) VALUES (N'627be471-252b-4ff1-be57-732ac063035a', N'0002', N'河北', N'李四', CAST(47.21 AS Decimal(18, 2))) 38 GO 39 INSERT [dbo].[Order] ([OrderId], [OrderCode], [Address], [UserName], [TotalPrice]) VALUES (N'50c2cd9a-191b-491f-ae1f-964b2ac345ea', N'0001', N'北京', N'张三', CAST(33.21 AS Decimal(18, 2))) 40 GO 41 INSERT [dbo].[OrderDetail] ([OrderDetailId], [OrderId], [ProductName], [Count], [Prcie]) VALUES (N'60a771ea-7f2d-4101-990d-72554b3dc3e2', N'627be471-252b-4ff1-be57-732ac063035a', N'iphone', 1, CAST(2.30 AS Decimal(18, 2))) 42 GO 43 INSERT [dbo].[OrderDetail] ([OrderDetailId], [OrderId], [ProductName], [Count], [Prcie]) VALUES (N'032a1e95-3903-4bc2-9629-af12a71a58b9', N'627be471-252b-4ff1-be57-732ac063035a', N'笔记本', 1, CAST(4.30 AS Decimal(18, 2))) 44 GO
3.代码
1 //4.one to many 2 using (SqlConnection connection = new SqlConnection(connectionString)) 3 { 4 string sql = "select * from [dbo].[Order] where orderid=@OrderId;select * from [dbo].[OrderDetail] where OrderId = @OrderId;"; 5 connection.Open(); 6 using (var multi = connection.QueryMultiple(sql, new { OrderId = "627BE471-252B-4FF1-BE57-732AC063035A" })) 7 { 8 var order = multi.Read<Order>().First(); 9 var orderDetail = multi.Read<OrderDetail>().ToList(); 10 } 11 }
最简单的这一部分就到这儿了,接着下来我会结合 dapper 的扩张库 将dapper 封装为一个 Helper