Q156343: PRB: Unknown Member Error Using Thisformset.ActiveControl

Article: Q156343
Product(s): Microsoft FoxPro
Version(s): WINDOWS:5.0,6.0
Operating System(s): 
Keyword(s): kbvfp kbvfp500 kbvfp600
Last Modified: 14-DEC-1999

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, versions 5.0, 6.0 
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SYMPTOMS
========

Referencing an active control with Thisformset.ActiveControl.<property or
method> generates the following error message in Visual FoxPro version 5.0:

  Unknown member ACTIVECONTROL

Referencing an active control in this manner does not generate an error in Visual
FoxPro 3.0 and 3.0b.

RESOLUTION
==========

Reference the active control as follows:

     Thisformset.ActiveForm.ActiveControl.<property or method>

This works properly in all versions of Visual FoxPro.

STATUS
======

This behavior is by design.

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

This is undocumented in Visual FoxPro 3.0 and is not intended to work, as
Formset objects do not have an ActiveControl property in any version of Visual
FoxPro.

Steps to Reproduce Behavior
---------------------------

1. Run the following code from a program (.prg) file:

     * Start of code example
     *
     PUBLIC oFormset
     oFormset = CREATEOBJECT('formset')
     oFormset.ADDOBJECT('form1','frm')
     oFormset.form1.VISIBLE=.T.
     oFormset.SHOW()

     DEFINE CLASS frm AS FORM
        CAPTION = "Click on Form to Demonstrate Error"
        ADD OBJECT text1 AS TEXTBOX WITH ;
           TOP = 100, ;
           LEFT = 120

        PROCEDURE CLICK
           * This will not generate an error in VFP 3.0 or 3.0b
           WAIT WINDOW THISFORMSET.ACTIVECONTROL.NAME TIMEOUT 3
        ENDPROC

     ENDDEFINE
     *
     * End of code example

2. Click anywhere on the form (outside of the text box).

3. In Visual FoxPro 5.0 or 6.0, the error "Unknown member ACTIVECONTROL"
  appears. In Visual FoxPro 3.0 or 3.0b, "TEXT1" is displayed in the WAIT
  WINDOW.

The preceding code works without error in any version of Visual FoxPro if
modified as follows:

        PROCEDURE CLICK
        * This will not generate an error in VFP 3.0, 3.0b, or 5.0
        WAIT WINDOW THISFORMSET.ACTIVEFORM.ACTIVECONTROL.NAME TIMEOUT 3
       ENDPROC

Additional query words:

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Keywords          : kbvfp kbvfp500 kbvfp600 
Technology        : kbVFPsearch kbAudDeveloper kbVFP500 kbVFP600
Version           : WINDOWS:5.0,6.0

=============================================================================

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