LINQ到实体EF4

Question

我有一组域模型name，desc和users（属于该组）收集

我试图让特定用户所属的所有组。这是我的LinQ声明：

var results = from p in AuthorizationService.UnitOfWork.Groups.FindAll() 
          where 
           (p.Users != null && p.Users.Select(u => u.Id).Contains(CurrentUser.Id)) 
          select p.Name; 

我收到以下错误，当我尝试执行查询

Cannot compare elements of type 'System.Collections.Generic.ICollection`1'. Only primitive types (such as Int32, String, and Guid) and entity types are supported. 

任何帮助是appreciated.Thanks！

Answer 1

删除用户对象的空测试，无论如何它是懒加载的，是您的用户虚拟？如果是，它是惰性加载，可以删除空测试然后

var results = 
from p in AuthorizationService.UnitOfWork.Groups.FindAll() 
where 
    p.Users.Any(u => u.Id == CurrentUser.Id) 
select p.Name; 

Answer 2

难道你不能走相反的路吗？

var results = AuthorizationService.UnitOfWork.Users.Include("Groups").First(u => u.ID == CurrentUser.Id).Select(u => u.Groups); 

希望这会有所帮助。