[英]How can i add var item in EF?
I have an array that its length is unspecified. 我有一个数组,其长度未指定。 Maybe 100 , 110 , ...
也许100,110,...
for each value i have : 对于每个值我都有:
int a1 = array[0];
var r1 = from row in db.products
where row.id == a1
select row;
int a2 = array[1];
var r2 = from row in db.products
where row.id == a2
select row;
...
How can i get summation of (r1 + r2 + r3 + ... (= sum))? 如何获得(r1 + r2 + r3 + ...(=和))的总和?
After this summation, i want to serialize: 总结之后,我想序列化:
string s1 = js.Serialize(sum);
You can do this in code: 您可以在代码中执行此操作:
Table: 表:
--use your db
USE [Breaz]
GO
/****** Object: Table [dbo].[theProducts] Script Date: 5/8/2017 3:49:33 PM ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[theProducts](
[theId] [int] IDENTITY(1,1) NOT NULL,
[id] [int] NULL,
CONSTRAINT [PK_theProducts] PRIMARY KEY CLUSTERED
(
[theId] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
GO
SET IDENTITY_INSERT [dbo].[theProducts] ON
GO
INSERT [dbo].[theProducts] ([theId], [id]) VALUES (1, 5)
GO
INSERT [dbo].[theProducts] ([theId], [id]) VALUES (2, 6)
GO
INSERT [dbo].[theProducts] ([theId], [id]) VALUES (3, 7)
GO
SET IDENTITY_INSERT [dbo].[theProducts] OFF
GO
program: 程序:
//use your database dbcontext
using (BreazEntities21 db = new BreazEntities21())
{
int[] a1 = { 5, 6 };
var r1 = (from row in db.theProducts
where a1.Contains((int)row.id)
select row).ToList();
int[] a2 = { 7 };
var r2 = (from row in db.theProducts
where a2.Contains((int)row.id)
select row).ToList();
var mergedList = r1.Union(r2).ToList();
var summation = mergedList.Sum(r => r.id);
var s1 = new JavaScriptSerializer().Serialize(summation);
}
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.