Trying to get hidden textbox from combobox

[SBendBuckeye]

Hello all,

I am trying to get a reference to the hiddent textbox behind a combobox using the following code. The handle changes but FromHandle(handle) line always returns Nothing.

<DllImport("user32", CharSet:=CharSet.Auto)> _
Private Shared Function FindWindowEx(ByVal hwndParent As IntPtr, _
                                     ByVal hwndChildAfter As IntPtr, _
                                     <MarshalAs(UnmanagedType.LPTStr)> _
                                     ByVal lpszClass As String, _
                                     <MarshalAs(UnmanagedType.LPTStr)> _
                                     ByVal lpszWindow As String) As IntPtr
  ' Function body should be empty.
End Function 'FindWindowEx

' Control is a ComboBox.
Public Shared Function GetHiddenTextBox(ByVal control As Windows.Forms.Control) As Control
  Dim handle As IntPtr = control.Handle
  If GetType(System.Windows.Forms.ComboBox).IsAssignableFrom(control.GetType) Then
    handle = FindWindowEx(handle, IntPtr.Zero, "EDIT", "" & Microsoft.VisualBasic.Chr(0) & "")
  End If
  Return System.Windows.Forms.Control.FromHandle(handle)
End Function 'GetHiddenTextBox

Does anyone have any ideas and/or suggestions? Thanks in advance!

Have a great day!

j2associatesNO_SPAM@gmail.com

 

[techsmith]

What are you actually trying to do? There may be a simpler solution than refering to this hidden control directly.

 

[SBendBuckeye]

Apparently this works in 2005 but not in 2003. When a user clears a combobox by selecting everything in the textbox and then deleting it, the combobox selected index is set to zero but the SelectedIndexChanged event is not fired. I was hoping to get the textbox and then set a handler to its changed event. Thanks for the response...

Have a great day!

j2associatesNO_SPAM@gmail.com

 

[techsmith]

You can probably get what you need using the ComboBox.KeyUp event or similar.