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Q194668: PRB: NewObject() Requires Null or "" for 2nd & 3rd Parameters

Article: Q194668
Product(s): Microsoft FoxPro
Version(s): WINDOWS:6.0
Operating System(s): 
Keyword(s): kbvfp600
Last Modified: 04-JAN-2000

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, version 6.0 
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SYMPTOMS
========

When using the NewObject() function, leaving any parameters blank while filling
subsequent parameters results in the following syntax error:

  Program Error.
  Function argument value, type, or count is invalid.

CAUSE
=====

Microsoft Visual FoxPro does not allow empty parameters in internal methods and
functions.

RESOLUTION
==========

When running the NewObject() function and passing an optional parameter, make
sure to pass "" or NULL in any optional parameter that precedes the one being
passed.

STATUS
======

This behavior is by design.

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

This functionality differs from the NewObject method. The NewObject method
allows for passing empty parameters because Visual FoxPro does allow empty
parameters when calling iDispatch methods from Component Object Model (COM)
objects.

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

Run the following code from a program file:

     CLEAR
     PUBLIC oX
     ********NewObject Method*************
     *!* The NewObject method allows blank arguments between those filled.
     oX = CreateObject('cst1','One')
     ?oX.cprop
     oX.NewObject('cst3','cst1',,,'Two') && Works
     ?oX.cst3.cprop

     ********NewObject Function Used Below***********
     oX=NewObject('cst1','','','Three')   && Works
     ?oX.cprop
     oX=NewObject('cst1',NULL,NULL,'Four') && Works
     ?oX.cprop
     oX=NewObject('cst1',,,'Five') && Fails with Syntax error
     ?oX.cprop
     *!* NewObject Function errors with blank arguments between those filled.
     DEFINE CLASS cst1 AS CUSTOM
        cprop = ''
        PROCEDURE INIT
           LPARAMETERS tctest
           THIS.cprop = tctest
       ENDPROC
     ENDDEFINE

Additional query words: kbVFp600 kbOOP

======================================================================
Keywords          : kbvfp600 
Technology        : kbVFPsearch kbAudDeveloper kbVFP600
Version           : WINDOWS:6.0
Issue type        : kbprb

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