Best way to convert a non-generic collection to generic collection

Question

What is the best way to convert a non-generic collection to a generic collection? Is there a way to LINQ it?

I have the following code.

public class NonG         


        

Answer 1

Since you can guarantee they're all TestClass instances, use the LINQ Cast method:

public static List ConvertToGenericClass(NonGenericCollection collection)
{
   return collection.Cast().ToList();
}

Edit: And if you just wanted the TestClass instances of a (possibly) heterogeneous collection, filter it with OfType:

public static List ConvertToGenericClass(NonGenericCollection collection)
{
   return collection.OfType().ToList();
}