LINQ到实体EF4 [英] Linq to Entities EF4

问题描述

我有 用户名，说明和收集组域模型（属于该组）

I have a Groups domain model with name,desc and collection of users(belonging to the group)

我想获得一个特定的用户所属的所有组。这是我的LinQ语句：

I am trying to get all groups that a particular user belongs to. This is my LinQ statement:

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

I get the following error when i try to execute the query

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！

Any help is appreciated.Thanks!

推荐答案

删除空测试用户反对，反正它的延迟加载，就是你的用户的虚拟？如果是这样，它是延迟加载，它的确定以删除空测试，然后

Remove the null testing for Users object, anyway it's lazy loaded, is your Users virtual? if it is, it is lazy-loaded, it's ok to remove the null testing then

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

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