PRB: Error 743 Adding ActiveX Controls to Control Collection

• Microsoft Visual Basic Learning, Professional, and Enterprise Editions for Windows, version 6.0

SYMPTOMS

When dynamically adding a large number of ActiveX controls into a Form's Controls Collection, you receive the following:

"Error 743. Unable to create or activate a new instance of <control name>."

RESOLUTION

While this situation has been reported as a bug, this is an application design problem and the best solution is "Don't do this." If you have encountered this problem, you are probably using controls where you should be using objects. Consider using a Class, ActiveX DLL, or ActiveX EXE to create your objects. If you must use controls, consider using windowless controls as they are less resource-intensive.

Keep in mind that forms with hundreds of visible controls will be confusing for the end user. If the controls are not being displayed, then there is no reason to use a control. ActiveX controls have a great deal of "overhead" when compared to an object.

STATUS

This behavior is by design.

MORE INFORMATION

Steps to Reproduce Behavior

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



2. Choose Add Project from the File menu to add an ActiveX Control project.



3. Place an instance of UserControl1 on Form1.



4. Place a CommandButton on Form1.



5. Add the following code to the module of Form1:

   
         Private Sub Command1_Click()
            Dim i As Integer
            On Error GoTo trap
            For i = 1 To 1000
               Me.Controls.Add "project2.usercontrol1", "control" & i
            Next
            Debug.Print "Finished"
            Exit Sub
            trap:
            If Err.Number = 743 Then
               Debug.Print "Error 743 loading control #" & i
            End If
         End Sub
    




6. Run the project. You should see the message in the immediate window indicating that the error occurred.

Additional query words: kbDSupport kbDSD kbVBp kbVBp600 kbCtrl

Keywords : kbGrpVB
Version :
Platform : WINDOWS
Issue type : kbprb