Beginning Programming with C++ For Dummies, 2nd Edition

Chapter 29

Are Virtual Functions for Real?

In This Chapter

Overriding between functions that are members of a class

Introducing virtual member functions

Binding early versus binding late

Declaring your destructor virtual — when and when not to do it

Inheritance gives users the ability to describe one class in terms of another. Just as important, it highlights the relationship between classes. I describe a duck as “a bird that …”, and that description points out the relationship between duck and bird. From a C++ standpoint, however, a piece of the puzzle is still missing.

You have probably noticed this, but a microwave oven looks nothing like a conventional oven and nor does it work the same internally. Nevertheless, when I say “cook,” I don’t want to worry about the details of how each oven works internally. This chapter describes this problem in C++ terms and then goes on to describe the solution as well.

Overriding Member Functions

It has always been possible to overload a member function with another member function in the same class, as long as the arguments differ:

  class ...