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Q133452: How to Use Macro Substitution in Object Referencing

Article: Q133452
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
=======

Macro substitution treats the contents of a memory variable or array element as
a character string literal. When an ampersand (&) precedes a Character-type
memory variable or array element, the contents of the variable or element
replace the macro reference. You can use macro substitution in any command or
function that accepts a character string literal.

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

In the Language Reference, page 8, the (&) Ampersand command is explained.
One area of amplification to the Macro Substitution command is the .cExpression,
which allows for a continuation of the command.

Here is an example showing how objects can be referenced using macro
substitution:

    frmForm = CREATEOBJECT("Form")
     frmForm.SHOW
     X="frmForm"
     cMemvarIs="Visible"
     &X.&cMemvarIs =.F. && Nothing happens due to improper syntax
     &X..&cMemvarIs=.F. && The form should disappear
     WAIT WINDOW "Form should have disappeared."
     madd="AddObject"
     &X..Visible=.T. && The form should reappear
     &X..&madd("cmdMyButton2","cmdMyButton")
     myb="cmdMyButton2"
     &X..&myb..&mvis=.t.
     READ EVENTS

     DEFINE CLASS cmdMyButton AS CommandButton
        PROCEDURE Click
        ThisForm.RELEASE
        CLEAR EVENTS
        ENDPROC
     ENDDEFINE


Additional query words: VFoxWin

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

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