Filtering derived classes in Entity set by OfType and getting exception

Question

I am trying to filter derived classes in my entities but i am getting exception.

var filtered = db.PersonSet.OfType<Person>().
               Where(person =>person.GetType()==typeof(Person))

I am getting below exception if i try to loop filtered collection by foreach.

"LINQ to Entities does not recognize the method 'System.Type GetType()' method, and this method cannot be translated into a store expression.".

How can i overcome it ? What can be alternative way for filtering ?

Answer 1

Try this:

var persons= db.PersonSet.OfType<Person>().ToList();
var filtered = persons.Where(person =>person.GetType()==typeof(Person))

This should work, but it's unnecessary. The first line should ensure that you only get objects of type Person.