c# - Entity Framework list of objects contains list of object lambda -

following scenario:

public class user{     public virtual icollection<mediaitem> mediaitems { get; set; } }  public enum emediaitemgenre {     [display(name = "pop")]     pop = 0,     [display(name = "other")]     other = 11 }  public class mediaitem {     public virtual icollection<mediaitemgenre> genres { get; set; } }  public class mediaitemgenre {     [key]     public int32 id { get; set; }      public emediaitemgenre genre { get; set; }      public int32 mediaitemid { get; set; }      public virtual mediaitem mediaitem { get; set; } } 

now following: have mediaitem , find mediaitems share same genre.

i did way:

list<mediaitem> litems = ltcontext.mediaitems.where(x => x.genres.any(y => pgenres.contains(y))).tolist(); 

but error

only primitive types or enumeration types supported in context.

the problem trying compare complex types in database list of complex types in memory, not possible. suggest doing converting pgenres list of int using projection:

list<int> pgenresid = pgenres.select(p => p.id).tolist(); 

then can use query:

list<mediaitem> litems = ltcontext.mediaitems          .where(x => x.genres.select(g => g.id).any(y => pgenresid.contains(y))).tolist(); 

now linq-to-entities can convert query putting int's of id's in queries.