DOCUMENT:Q176429 07-NOV-1997 [vbwin] TITLE :BUG: Can't Check MDIChild Property of Forms in Forms Collection PRODUCT :Microsoft Visual Basic for Windows PROD/VER:WINDOWS:5.0 OPER/SYS:WINDOWS KEYWORDS:vb5all kberrmsg ====================================================================== --------------------------------------------------------------------- The information in this article applies to: - Microsoft Visual Basic Learning, Professional, and Enterprise Editions for Windows, version 5.0 --------------------------------------------------------------------- SYMPTOMS ======== The following code worked in Visual Basic 4.0, but fails in Visual Basic 5.0 with an error "Error 380, Invalid Property Value" if an MDI parent form is in the project: Dim f As Form For Each f In Forms If f.MDIChild Then Form1.Print f.Name & " MDI Child" Else Form1.Print f.Name & " Not MDI Child" End If Next CAUSE ===== MDI forms do not have an MDIChild property in either Visual Basic 4.0 or Visual Basic 5.0. Visual Basic 4.0 compensated for that in the specific case of looping through the forms collection and checking this property, but Visual Basic 5.0 does not. RESOLUTION ========== The workaround is to determine if the form is an MDI form before checking the MDIChild property, which the following code demonstrates: Dim f As Form For Each f In Forms If Not TypeOf f Is MDIForm Then If f.MDIChild Then Form1.Print f.Name & " MDI Child" Else Form1.Print f.Name & " Not MDI Child" End If Else Form1.Print f.Name & " Not MDI Child" End If Next STATUS ====== Microsoft has confirmed this to be a bug in the Microsoft products listed at the beginning of this article. We are researching this bug and will post new information here in the Microsoft Knowledge Base as it becomes available. ====================================================================== Keywords : vb5all kberrmsg Version : WINDOWS:5.0 Platform : WINDOWS Issue type : kbbug ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY. Copyright Microsoft Corporation 1997.