mshd.net
当前位置:首页 >> C linq or >>

C linq or

SQL:select * from A,B where A.cpID=B.cpID and A.cbID=B.cbID LINQ:var p = from t1 in a from t2 in b from t3 in c where t1.cpid equal t2.cpid and t1.cbid equal t3.cbid select new { t1, t2.cpid }

SumA = (from c in vSession.Linq() select c.a).Sum(); CountB = (from c in vSession.Linq() select c.b).Count(); ------解决方案-------------------- C# code//更改成这种形式 var query = from w in data.News select new { sum=data.News...

var testcase =(from c in men.testcase where c.planid==planId orderbyDescing c.caseset_loop select c).FirstOrDefault() ;

LINQ 按多个字段排序(orderby、thenby、Take) orderby 子句解析为 OrderBy()方法,orderby descending 子句解析为OrderBy Descending()方法: var racers = Formula1.GetChampions(). Where(r = > r.Country == "Brazil"). OrderByDescending(...

public List GetList() var query = from c in context.Sys_VehicleManage select new Sys_VehicleManage { VehicleID = c.VehicleID, VehicleNumber = c.VehicleNumber }; return query.Where(p=>p.VehicleID==1).ToList(); try it

select new 出来的是一个匿名对象,也就是包含c.ContactName跟o.OrderID这两个字段的对象。 如果你直接select c,只能选择Customers 中的字段,无法提取Orders 中的,而你的查询结果要求同时提取Customer的ContactName跟Order的OrderID 。

错误代码:var orders = db.Orders.Where(o => o.UserId == userid).Select(c => new Order { OrderId = c.OrderId, OrderDate = c.OrderDate, Total = c.Total, OrderDetails = db.OrderDetailss.Where(od => od.OrderId == c.OrderId).ToList(...

var q = from c in db.Customers where c.City == "London" select c 等价于SQL语句 select * from db.Customers c where c.City = "London" 然后把记录集赋给变量q foreach (var v in q) 表示记录集q里的每一条记录v要执行下马{}里的操作

query = from c in tbs where c.sx != "类别" && c.path_tbname.Contains(tName.Text) orderby c.id select c; Contains 等于 like '%'+tName.Text+'%'

public static void cs() { System.Data.DataTable dt = new System.Data.DataTable(); dt.Rows.Add(""); var quer = from tb in dt.AsEnumerable() group tb by tb.Field("xx") into x select new{ a=x.Key, b=x }; foreach(var c in quer) { i...

网站首页 | 网站地图
All rights reserved Powered by www.mshd.net
copyright ©right 2010-2021。
内容来自网络,如有侵犯请联系客服。zhit325@qq.com