Look at this..

VB Code:
  1. Private Declare Function GetAsyncKeyState Lib "user32" (ByVal vKey As Long) As Integer

  2.  
  3. Private Sub Command1_Click()

  4.  
  5.     If GetAsyncKeyState(13) Or GetAsyncKeyState(vbKeySpace) Then

  6.         Exit Sub   '(Don't compute this click)

  7.     End If

  8.     MsgBox "Clicked!" 'Compute this click!

  9. End Sub