c# - Get all items of a certain type from a List of abstract type

Question

I have a List<> of abstract objects that contains different types of objects. I am trying to grab all the items of a certain type and set those items to their own List<>.

This is not working -

//myAbstractItems is a List<myAbstractItem>
//typeAList inherents from myAbstractItem


var typeAList = ((List<itemTypeA>)myAbstractItems.Where(i => i.GetType() == typeof(itemTypeA)).ToList());

The casting (List<itemTypeA>) appears to be failing.

Answer 1

Use the OfType extension method:

var typeAList = myAbstractItems.OfType<itemTypeA>().ToList();

From the documentation...

The OfType(IEnumerable) method returns only those elements in source that can be cast to type TResult.