OOP illustrations from Microsoft Visual FoxPro 6.0: Programmer’s Guide

Microsoft Press’s Microsoft Visual FoxPro 6.0: Programmer’s Guide1998 illustrates concepts of object-oriented programming with phones.

Contents

Class/object

An old-fashioned rotary dial phone next to its schematic.

Encapsulation

A rotary dial phone with half of its front removed revealing the inside.

Subclassing

A rotary dial phone at the top with lines leading to five different phones at the bottom (push button phone, fax, cell phone, etc.).

Inheritance

Phones with dials on the left become identical phones with buttons on the right.