Option Explicit
Declare Function SetTimer Lib "user32" (ByVal hwnd As Long, _
  ByVal nIDEvent As Long, ByVal uElapse As Long, _
  ByVal lpTimerFunc As Long) As Long
 
Declare Function KillTimer Lib "user32" (ByVal hwnd As Long, _
  ByVal nIDEvent As Long) As Long
 
Declare Function GetAsyncKeyState Lib "user32" _
  (ByVal vKey As Long) As Integer
 
<font color=green>' Prüfen, welche Taste gedrückt wurde</font>
Function GetKey() As String
  Dim i As Integer
 
  For i = 32 To 250
    <font color=green>' Falls Taste gedrückt...</font>
    If GetAsyncKeyState(i) <> 0 Then
      GetKey = Chr$(i)
      Exit For
    End If
  Next i
End Function
 
<font color=green>' Diese Routine wird vom API-Timer aufgerufen
' Hier werden die Tasten protokolliert</font>
Sub TimerProc(ByVal hwnd As Long, ByVal nIDEvent As Long, _
  ByVal uElapse As Long, ByVal lpTimerFunc As Long)
 
  Dim sKey As String
  Static sOldKey As String
 
  sKey = GetKey()
  If sKey <> sOldKey Then
    sOldKey = sKey
    Form1.Text1.Text = Form1.Text1.Text & sKey
  End If
End Sub

Option Explicit
 
Private Sub Command1_Click()
  <font color=green>' API-Timer erstellen</font>
  SetTimer Me.hwnd, 0, 1, AddressOf TimerProc
  Text1.Text = ""
End Sub
 
Private Sub Command2_Click()
  <font color=green>' API-Timer löschen</font>
  KillTimer Me.hwnd, 0
End Sub
 
Private Sub Form_Unload(Cancel As Integer)
  <font color=green>' API-Timer löschen</font>
  KillTimer Me.hwnd, 0
End Sub