Q177094: PRB: ActiveX Control Cannot Assign Run-Time Read-Only Property

Article: Q177094
Product(s): Microsoft Visual Basic for Windows
Version(s): 
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 Learning Edition for Windows, versions 5.0, 6.0 
- Microsoft Visual Basic Professional Edition for Windows, versions 5.0, 6.0 
- Microsoft Visual Basic Enterprise Edition for Windows, versions 5.0, 6.0 
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SYMPTOMS
========

When your Usercontrol attempts to expose a run-time read-only property of a
constituent control, you get the following error:

  Compile Error:
  Can't Assign to Read-Only Property

CAUSE
=====

The run-time read-only properties of constituent controls cannot be exposed.

Because properties of the UserControl object and constituent controls are exposed
by delegation, you cannot expose design-time-only properties such as Appearance
and ClipControls. The settings you choose for such properties will be fixed for
your ActiveX control.

STATUS
======

This behavior is by design.

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

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

1. Start a new ActiveX Control project in Visual Basic. UserControl1 is created
  by default.

2. Add a text box to UserControl1.

3. Copy the following code to the Code window of UserControl1:

        Option Explicit
        Property Let Multiline(b As Boolean)
           Text1.Multiline = b
        End Property

        Property Get Multiline() As Boolean
           Multiline = Text1.Multiline
        End Property

4. Close UserControl1.

5. Add a Standard EXE project to the project group by completing the following
  steps:

  1. From the File Menu, click Add Project. The Add Project dialog box
     displays.

  2. Click Standard EXE and click Open to close the Add Project dialog box and
     open the Form1 form of the second project.

6. Add Usercontrol1 to Form1.

7. In the Properties window for the Usercontrol, attempt to set the MultiLine
  property to True and note that you receive the compile error described above.

REFERENCES
==========

"Exposing Properties of Constituent Controls", Books Online

Additional query words: kbVBp500 kbVBp600 kbVBp kbdsd kbDSupport KBCONTROL KBCTRLCREATE

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Keywords          : kbGrpDSVB 
Technology        : kbVBSearch kbAudDeveloper kbZNotKeyword6 kbZNotKeyword2 kbVB500Search kbVB600Search kbVBA500 kbVBA600 kbVB500 kbVB600
Issue type        : kbprb

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