SQL Linq与包含列表中的项目

Question

这是我的代码：

CommissionCalculationDataContext dc = new CommissionCalculationDataContext();
CrossAppDataContext dc2 = new CrossAppDataContext();
List<Group_ADUser_Mapping> mapList = (from a in dc.Group_ADUser_Mappings where a.GroupID == '3' select a).ToList();
List<ADUser> userList = (from a in dc2.ADUsers where mapList.Contains(a.sAMAccountName) select a).ToList();  //doesnt work

目标是，我得到了一个映射列表，然后只需要获取此映射列表中的User（通过SAMAccountName）

错误是：出现OVerload问题...。

因此，实际上我想将Group_ADUser_Mappings.sAMAccountName与ADUser.sAMAAccountName进行比较。

Answer 1

尝试

List<String> mapList = dc.Group_ADUser_Mappings.Where(x =>  x.GroupID == '3').Select(y => y.sAMAccountName).ToList();
List<ADUser> userList = dc2.ADUsers.Where(x => mapList.Contains(x.sAMAccountName)).ToList();

为了避免List.Contains大小写问题，您可以随后进行过滤。 这应该工作（未试用）：

userList = userList.Where(x => mapList.Any(y => y.sAMAccountName == x.sAMAccountName)).ToList();

Answer 2

您可以只加入两个实体并选择您的ADUser吗？

List<ADUser> userList = (from a in dc2.ADUsers 
    join b in dc.Group_ADUser_Mappings  on a.sAMAccountName equals b.sAMAccountName 
    where b.GroupID == "3" 
    select a).ToList();