Inheritance and Casting

[Richard Andrew x64]

Suppose I have the following class:

class C : public A, public B
{
}

Assuming that class B is a pure virtual class, should I be able to cast objects of type C to B in order to call C's implementations of B's abstract methods? In other words, can I do:

C* obj = new C();
DWORD z = ((B*)obj)->GetValue();

What I want to do is effectively add my own custom interface to existing MFC classes and then use those objects generically.

The difficult we do right away... ...the impossible takes slightly longer.