c# - 从 TSQL 切换到 LINQ

Question

我正在尝试将下面的 TSQL 转换为 LINQ。我显然不太擅长这一点，也不知道如何在 Linq 中加入。我的困惑不仅仅是简单的表达。在我的基本用途中，我的结果集是一个当然代表表格行的类......但是连接不会有这个一对一的比例，所以我必须创建一个自定义结果集吗？

TSQL：

SELECT 
  SimEA.*,
  SimE.*
FROM 
  dbo.SSimEmailsAdressees SimEA

JOIN dbo.SSimEmails SimE ON
SimEA.EmailID = SimE.EmailMsgID

WHERE
 SimEA.UserId = var

我最接近的：

this.GetAll<SSimEmails>() 
    .Where(e => e.SSimEmailsAdressees.Any(p => p.UserId.ToString() == usrID));

这当然会返回一个模拟被查询的单个表的对象。所以我需要帮助来添加连接，我猜我必须创建一个类似这样的返回对象？

this.GetAll<MyJoinResultsObject>......

Answer 1

我认为你应该写这样的东西：

var q = 
        from SimEA in SSimEmailsAdressees
        where SimEA.UserId = usrID
        join SimE in SSimEmails on SimEA.EmailID equals SimE.EmailMsgID
               into joinSimE
        from SimE in joinSimE.DefaultIfEmpty() 
        select new { EmailID = SimEA.EMailID, UserId = SimEA.UserId, OtherField = SimE.OtherField }; 

Answer 2

var result = from ea in SimEA
         join e in SimE
         on ea.EmailID equals e.EmailMsgID
     where ea.UserId = userId
         select new { properties you want here or new object based on properties}