Getting reference to control with focus

I'm trying to implement a cut/copy/paste menu into our application and I'm having trouble trying to determine what the current control that has focus.

I've done all the 'hard' bits by making the application clipboard aware (WM_DRAWCLIPBOARD) and have full capability for custom clipboard data etc. but I just cannot get the last piece of the puzzle to work! The application is built up from extensible components. I'm trying to provide a means for all 'clipboard aware' controls (textbox, combo, etc.) in the application to have it 'for free'. i.e. I don't want to mandate a custom textbox instead of the WinForms one (some of the application extensions may be 3rd party for example).

In my form's WndProc (C# form overriden method) I've been trapping the WM_PARENTNOTIFY message and then calling GetFocus() and then Control.FromChildHandle() to obtain what I thought would be the active control. However I notice that GetFocus() is returning a handle to the previous control. If I click on the control again the Control is returned as the one I think it is. If I click off the control on to another then it's the same 1st event is the old control and the 2nd time I click it's the 'new' control.

Here's a few snippets of code:

case WM_PARENTNOTIFY:
if( (int) m.WParam == WM_LBUTTONDOWN )
{
   // Attempt to update the menu state
   ConfigureMenu();
}

//---

Control ctlFocus = GetControlWithFocus();
TextBoxBase textBox = ctlFocus as TextBoxBase;
if( textBox != null )
{
   // It's a textbox so basic text paste is possible, check that the clipboard has text data...
}

//---

Control controlWithFocus = null;

// Obtain a handle to the control that currently has focus
IntPtr handleControl = GetFocus();
if( handleControl != IntPtr.Zero )
{
// Obtain the control fro the handle
controlWithFocus = Control.FromChildHandle( handleControl );
}
return controlWithFocus;

Our custom controls handle the request differently so will always work but I need a solution for the standard .NET Framework controls which have built-in clipboard support (such as anything derived from TextBoxBase).

It's a bit late so perhaps I've missed something obvious but does anyone have any advice Thanks in advance!

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Getting reference to control with focus

Getting reference to control with focus

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