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Q138504: PRB: "Data type mismatch" Error When Running a Form

Article: Q138504
Product(s): Microsoft FoxPro
Version(s): WINDOWS:3.0
Operating System(s): 
Keyword(s): 
Last Modified: 11-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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SYMPTOMS
========

One of the following error messages appears when running a form:

- Data type mismatch.

-or-

- Error loading file - ControlSource - record number #. Data type is invalid
  for this property.

CAUSE
=====

The memory variable created by the ControlSource property of one or more objects
on the form is the same as the memory variable that refers to the form.

RESOLUTION
==========

Either rename the form, or change the ControlSource value to something other
than the name of the form.

STATUS
======

This behavior is by design.

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

All memory variables must be unique. When a form is run, a memory variable is
created that has the same name as the form. When the ControlSource of an object
evaluates to a memory variable, Visual FoxPro attempts to create a memory
variable. Because a memory variable of the same name already exists, Visual
FoxPro produces the error.

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

1. Create a form called myform.

2. Add a combo box.

3. Set the ControlSource property of the combo box to myform.

4. Run the form.

Additional query words: VFoxWin

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

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