Linq - How to select items from a list that contains only items of another list?

Question

I have this two classes:

public class Item
{
   public int Id{get;set;}
   public List<Test> TestList{get;set;} 
}
public class Test
{ 
   public int Id{get;set;}
   public Item Item{get;set;}
   public byte State{get;set;}
}

Answer 1

这将返回所有状态都在stateList ，我认为这就是您所需要的：

Items.Where(x => x.TestList.All(s => stateList.Contains(s.State)));

Answer 2

如果您只需要TestList只有状态为2的项目的项目：

tems.Where( i => i.TestList.All(li => li.State == 2))

Answer 3

I have similar issue:

List<string> mds = _userService.GetAllMDUsers();
conf = _context.BillingsConfirmationsView.Where(c=> mds.Contains(c.EmployeeShort.ToUpper()));