PRB: Syntax Error with ActiveX Control Terminates VFP

ID: Q156505

The information in this article applies to:

Microsoft Visual FoxPro for Windows, versions 5.0, 6.0

SYMPTOMS

The ImageList ActiveX control is used to store a set of images for use with other ActiveX controls. When setting the Picture property of an ActiveX control to an image in the ImageList control, the following error may occur:

This Program has performed an illegal operation and will be shut down

CAUSE

The Picture property may have been omitted from the reference to the ImageList control.

STATUS

Microsoft is researching this behavior and will post new information here in the Microsoft Knowledge Base as it becomes available.

MORE INFORMATION

The ImageList ActiveX control allows you to load all the .bmp files and .ico files that may be needed for other ActiveX controls. You can then set the Picture property of an ActiveX control to reference any of the images in the ImageList control. The following command is an example of assigning the first image to the Picture property of an ActiveX control:


   ThisForm.Olecontrol1.Object.Picture = ;
     ThisForm.Olecontrol2.Object.ListImages(1).Picture

If the Picture property is omitted from the end of the reference, the following error message occurs:

This Program has performed an illegal operation and will be shut down

Steps to Reproduce Behavior

The following program demonstrates the correct and incorrect way to change a Picture Property of an ActiveX control using an image from the ImageList control.


    ***** Start Code *****

   PUBLIC frmOcxTest
   frmOcxTest = CREATEOBJECT('Form1')
   frmOcxTest.ADDOBJECT("PicList1","PicList", ;
      "COMCTL.ImageListCtrl.1")

   * Add the Fox.bmp to the image control
   frmOcxTest.PicList1.Object.ListImages.Add ;
      (,,LoadPicture("C:\VFP50\FOX.BMP"))
   frmOcxTest.ADDOBJECT("OcxButton1","OcxButton", ;
      "Threed.SSCommand")
   frmOcxTest.OcxButton1.Caption = "Change Image Works"
   frmOcxTest.ADDOBJECT("Button1","Button")

   frmOcxTest.Show()

   DEFINE CLASS Form1 AS Form
      Top = 0
      Left = 0
      Height = 300
      Width = 300
      Name = "Form1"
      Caption = "ImageList Test"

   ENDDEFINE

   DEFINE CLASS PicList AS OLEControl
   ENDDEFINE

   DEFINE CLASS OcxButton AS OLEControl
      Top = 75
      Left = 75
      Height = 80
      Width = 150
      Visible = .T.
      PROCEDURE Click
        * This code will change the image on the ActiveX Button
        ThisForm.OcxButton1.Object.Picture = ;
          ThisForm.PicList1.Object.ListImages(1).Picture
      ENDPROC
   ENDDEFINE

   DEFINE CLASS Button AS CommandButton
      Top = 195
      Left = 75
      Height = 27
      Width = 150
      Visible = .T.
      Caption = "Change Image Fails"

      PROCEDURE Click
        * This code will cause the following error message:
        *  "This Program has performed an illegal operation and will be
        *  shut down" (There is no "Picture" reference after "ListImages".)

        ThisForm.OcxButton1.Object.Picture = ;
          ThisForm.PicList1.Object.ListImages(1)
      ENDPROC
   ENDDEFINE

   ***** End Code *****

When you run the above code, the "Change Image Works" button displays the Fox.bmp file from the ImageList control. The "Change Image Fails" button causes an "Invalid Page Fault" error.

In Visual FoxPro 6.0, you do not get the "Invalid Page Fault" error, instead you get the following error message:

Ole exception error: Exception code c0000005. OLE object may be corrupt

REFERENCES

For more information on the ActiveX controls that shipped with Visual FoxPro 5.0, see Help and the Ctrlref.hlp file located in the Vfp\Ctrlhlp directory.

Additional query words:

Keywords : kbActiveX kbVFp500 kbVFp600 FxprgGeneral
Version : 5.0, 6.0
Platform : WINDOWS
Issue type :