[AccessD] A2K: Trap Key stroke

Hello all
I have some key down code to trap key strokes. Pretty basic stuff
What do I type after I have trapped the key stoke eg F1 to stop any further processing?

Many thanks in advance

Darren

EG  <snip>
Private Sub Form_KeyDown(KeyCode As Integer, Shift As Integer)

        Select Case KeyCode
            Case vbKeyF1
            'What do I type here to stop the processing of (In this case F1)            
            'I DON'T wanna see the help screen
            Case vbKeyF2
            blah blah blah