Private Declare Function GetAsyncKeyState Lib "user32" Alias "GetAsyncKeyState" _
  (ByVal vKey As Long) As Integer
 
Private Const VK_RBUTTON = &H2
Private Const VK_LBUTTON = &H1
Private Const VK_MBUTTON = &H4             '  NOT contiguous with L RBUTTON
 
Private Type POINTAPI
        x As Long
        y As Long
End Type
 
 
Private Sub Form_Load()
     Timer1.Interval = 50 '50 Millisekunden
End sub
 
Private Sub Timer1_Timer()
    Dim Result As Long
 
    If  GetMPts(VK_RBUTTON).X = 1 Then Msgbox "Rechte Maustaste gerade gedrückt"
    If  GetMPts(VK_LBUTTON).X = 1 Then Msgbox "Linke Maustaste gerade gedrückt"
    If  GetMPts(VK_MBUTTON).X = 1 Then Msgbox "Mittlere Maustaste" & _
      "geradegedrückt"
 
    If  GetMPts(VK_RBUTTON).Y = 1 Then Msgbox "Rechte Maustaste wurde gedrückt"
    If  GetMPts(VK_LBUTTON).Y = 1 Then Msgbox "Linke Maustaste wurde gedrückt"
    If  GetMPts(VK_MBUTTON).Y = 1 Then Msgbox "Mittlere Maustaste wurde" & _
      "gedrückt"
End Sub
 
Private Function GetMPts(Byval nvkKey As Long) As POINTAPI
 Dim Longwert As Long
 Dim x As Integer
 Dim y As Integer
 
 Longwert = GetAsyncKeyState(nvkKey)
 
 If (Longwert And &H8000&) = 0 Then
   x = Longwert And &HFFFF&
   y = Longwert / &H10000
 Else
   x = &H8000 Or (Longwert And &H7FFF&)
   y = (Longwert And &H7FFF&) / &H10000
 End If
 
 GetMPts.x = x
 GetMPts.y = y
End Function