Teach Yourself Borland C++ in 14 Days - portal

Totally Immersed: C++ Classes and Object-Oriented Programming
Workshop
Sometimes it’s necessary to take a couple days off and let it all soak in.
In fact, if I thought I could get by with it I’d make Day 5 a blank
chapter called “A Day of Rest.” Take it a little at a time, and one of
these days you’ll be just like Archimedes—you’ll be running around
your office or your house shouting “Eureka!” because the light just
came on in your noggin. But keep track of your clothes, will you? The
neighbors could be watching.
The Workshop contains quiz questions to help you solidify your understanding of the
material covered and exercises to provide you with experience in using what you have learned.
You can find answers to the quiz questions in Appendix A, “Answers to Quiz Questions.”
Q&A
Q How can I keep a class member function private to the outside world but
allow derived classes to call it?
A Make it protected. A protected function is not accessible to users of your class but
is accessible to derived classes.
Q What does data abstraction mean?
A Data abstraction means hiding the details of the class that the users of the class
don’t need to see. A class might have dozens of data members and functions, but
only a few that the user can see. Make visible (public) only the functions that a user
needs to know about to use the class.
Q What is an object?
A Effectively speaking, an object is any block of code that can be treated as a separate
entity in your programs. An object in C++ generally means a class. In C++Builder,
that definition is expanded to include VCL components. OCX and ActiveX
controls could also be considered objects.
Q Can my class have more than one constructor?
A Yes. Your class can have as many constructors as needed, provided that you follow
the rules of function overloading.
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