Q128633: How Inheritance Affects PROTECTED Methods and Properties

Article: Q128633
Product(s): Microsoft FoxPro
Version(s): WINDOWS:3.0
Operating System(s): 
Keyword(s): 
Last Modified: 12-FEB-2000

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, version 3.0 
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SUMMARY
=======

This article explains how protected properties and methods are inherited when a
class is derived from another class definition. It specifically addresses these
issues:

- Whether a protected class member is inherited and thus visible to a derived
  class.

- Whether it is possible to modify the protected status of a member variable.

MORE INFORMATION
================

Members variables (properties) or procedures (methods) are by default visible
outside a class definition. Once an object has been instantiated, its properties
and methods can be accessed by other objects. The PROTECTED keyword prevents
access to the Object's properties and methods from outside the object's
definition.

A PROTECTED property or method is visible to the member functions of the class
that declared these members, and it is visible to the member functions of a
class derived from this class. In other words, protected properties, objects
members, and methods are inherited.


When PROTECTED members are inherited, they still have a PROTECTED status.
Although it is possible to redefine the content of properties and methods in a
derived class, the PROTECTED status of a member variable cannot be overridden.
If you need to modify this status in a subclass, you can add a member variable
to the class. The goal of the new property or method that is visible to other
objects is to access the PROTECTED member variable from within the class
definition.

Additional query words: VFoxWin 3.00

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Keywords          :  
Technology        : kbVFPsearch kbAudDeveloper kbVFP300
Version           : WINDOWS:3.0

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