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Q150230: FIX: "Function call on Left-hand side of assignment…" Error

Article: Q150230
Product(s): Microsoft Visual Basic for Windows
Version(s): WINDOWS:4.0
Operating System(s): 
Keyword(s): kbGrpDSVB
Last Modified: 11-JAN-2001

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The information in this article applies to:

- Microsoft Visual Basic Standard Edition, 32-bit, for Windows, version 4.0 
- Microsoft Visual Basic Professional Edition, 16-bit, for Windows, version 4.0 
- Microsoft Visual Basic Professional Edition, 32-bit, for Windows, version 4.0 
- Microsoft Visual Basic Enterprise Edition, 16-bit, for Windows, version 4.0 
- Microsoft Visual Basic Enterprise Edition, 32-bit, for Windows, version 4.0 
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SYMPTOMS
========

When a Read-Only property of a Text box is set in code, trying to run a project
brings up the following error message:

  "Function call on left-hand side of assignment must return Variant or Object"

The environment shows a line of code that does not involve a property where an
object or variant is necessary.

CAUSE
=====

The problem with the code has nothing to do with the return value of a function.
Although the error message is misleading and incorrect, it is an error to try
and set a Read-Only property.

RESOLUTION
==========

Do not attempt to set a Read-Only property in code (by definition).

STATUS
======

Microsoft has confirmed this to be a bug in the Microsoft products listed at the
beginning of this article. This bug has been fixed in Visual Basic 5.0.

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

Steps to Reproduce Problem
--------------------------

1. Start a new project in Visual Basic 4.0. Form1 is created by default.

2. Add a TextBox control to Form1.

3. In the Form_Load event, place the following code:

        Private Sub Form_Load()
           Text1.HideSelection = False
        End Sub

4. Run the program by pressing the F5 key. The error message occurs.

Additional query words: kbVBp400bug kbVBp500fix kbVBp kbdsd kbDSupport

======================================================================
Keywords          : kbGrpDSVB 
Technology        : kbVBSearch kbAudDeveloper kbVB400Search kbVB400 kbVB16bitSearch
Version           : WINDOWS:4.0
Issue type        : kbbug
Solution Type     : kbfix

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