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Q134641: DOCERR: Calling Parent Class Method Code Example Is Incorrect

Article: Q134641
Product(s): Microsoft FoxPro
Version(s): WINDOWS:3.0
Operating System(s): 
Keyword(s): 
Last Modified: 15-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
=======

The Scope Resolution examples shown in the Developer's Guide, page 272, "Calling
Parent Class Method Code," are not correct for the released version of Visual
FoxPro version 3.0.

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

In the Developer's Guide, on page 272, there are two specific examples to call
parent class code from the VCR visual class provided as a sample with Visual
FoxPro version 3.0. The message being issued does not properly reference the
object to which the message is being sent.

The first example, cmdNav::Click(), causes a "This object does not inherit from
class CMDNAV" error message. The correct command to execute is:

     VCR.cmdTop::Click

In this particular case, the actual name of the parent class (VCR) and the member
of that parent (cmdTop) must be explicitly used in order to properly reference
the object where the method to execute is located.


The second example, =EVAL(this.ParentClass + '::Click()', on Page 272 causes a
"Missing Expression" error message. The syntax should be:

     =EVAL(This.Parent.Class+"."+This.Name+"::click()")

In this example, This.Parent.Class evaluates to VCR, which is the container
Class. And This.Name evaluates to the name of the current object (cmdTop). The
result of the evaluation is the same message identified in the first example,
VCR.cmdTop::Click.

Additional query words: 3.00 VFoxWin OOP

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

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