Knowledge Base

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

Article ID: 150230

Article Last Modified on 7/13/2004

Microsoft Visual Basic 4.0 Standard Edition
Microsoft Visual Basic 4.0 Professional Edition
Microsoft Visual Basic 4.0 Professional Edition
Microsoft Visual Basic 4.0 16-bit Enterprise Edition
Microsoft Visual Basic 4.0 32-Bit Enterprise Edition

This article was previously published under Q150230

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

Start a new project in Visual Basic 4.0. Form1 is created by default.
Add a TextBox control to Form1.

In the Form_Load event, place the following code:

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

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

Additional query words: kbVBp400bug kbVBp500fix kbVBp kbdsd kbDSupport

Keywords: kbbug kbfix KB150230