Can 't create extesion method for LINQ to Enitities link DeleteAllOnSubmit() in LINQ to SQL

Answer 1

Try this. The method needs to be a generic, TEntity is simply the placeholder for the type.

public static void DeleleAllObjects<TEntity>( this ObjectSet<TEntity> objectSet,
                                              IEnumerable<TEntity> objects)
    where TEntity : class
{

   foreach(var o in objects)
   {
      objectSet.DeleteObject(o);
   }
}