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Q129790: Base Classes Available in Visual FoxPro

Article: Q129790
Product(s): Microsoft FoxPro
Version(s): WINDOWS:3.0
Operating System(s): 
Keyword(s): 
Last Modified: 10-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
=======

All Visual FoxPro base classes recognize a minimum set of events and properties.
You can create objects or derive subclasses from most of the Visual FoxPro base
classes, but not all.

This article lists the Visual FoxPro base classes, indicates whether or not each
class can be subclassed, lists the minimum event set for Visual FoxPro base
classes, and lists the minimum property set for Visual FoxPro base classes.

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

Visual FoxPro Base Classes That Can Be Subclassed
-------------------------------------------------

The following Visual FoxPro Classes are not an integral part of a parent
container, so they can be subclassed in the Class Designer:

 check box        EditBox        list box              Shape
 Column (1)       Form           OLEBoundControl       Spinner
 CommandButton    FormSet        OLEContainerControl   text box
 CommandGroup     Grid           Timer                 ComboBox
 OptionGroup      ToolBar        Container             Image Control
 Label            PageFrame      Custom                Line

Visual FoxPro Base Classes That Cannot Be Subclassed
----------------------------------------------------

The following Visual FoxPro Classes are an integral part of a parent container,
so they cannot be subclassed in the Class Designer:

 Header
 OptionButton
 Page
 Separator

Base Class Minimum Event Set
----------------------------

All Visual FoxPro base classes recognize the following minimum set of events:

 Event   - Description
-----------------------
 Init    - Invoked when the object is created.
 Destroy - Invoked when the object is released from memory.
 Error   - Invoked when an error occurs in event or method procedures
           of the class.

Base Class Minimum Property Set
-------------------------------

All Visual FoxPro base classes have the following minimum set of properties:

 Property     -  Description

 Class        -  What type of class it is.

 BaseClass    -  The base class it was derived from, such as Form,
                 Commandbutton, Custom, and so on.

 ClassLibrary -  The class library the class belongs to.

 ParentClass  -  The class the object was derived from. If the class was
                 derived directly from a Visual FoxPro base class, the
                 ParentClass property is the same as the BaseClass
                 property.

NOTE: Most of the information in this article is available under many different
topics in the Visual FoxPro Help file.

Additional query words: VFoxWin 3.00

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

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