LINQ 相当于 SQL 的“IN”关键字

如何在 linq 中编写下面的 sql 查询

select * from Product where ProductTypePartyID IN
(
    select Id from ProductTypeParty where PartyId = 34
)

LINQ 中没有直接的等效项。相反，您可以使用 contains () 或任何 其他实现它们的技巧。这是一个使用的示例Contains:

String [] s = new String [5];
s [0] = "34";
s [1] = "12";
s [2] = "55";
s [3] = "4";
s [4] = "61";

var  result = from d in  context.TableName
              where s.Contains (d.fieldname)
              select d;

检查此链接了解详细信息：in 子句 Linq

int[] productList = new int[] { 1, 2, 3, 4 };


var myProducts = from p in db.Products
                 where productList.Contains(p.ProductID)
                select p;