Answer Posted / mahfuzur rahman

Virtual function vs pure virtual function :

Virtual function :-

1. Virtual function have a function body.
2. Overloaded can be done by the virtual funciton.
(Optional)
3. It is define as : virtual int myfunction();


Pure virtual function :-

1. Pure virtual function have no function body.
2. Overloading is must in pure virtual funciton. (Must)
3. It is define as : virtual int myfunction() = 0;
4. A class is "abstract class" when it has at least one
pure virtual function.
5. You cann't create instance of "abstract class", rather
you have to inherit the "abstract class" and overload all
pure virtual function.

Like :- CControlBar class is an "abstract class".

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