Private Function PreFilterMessage(ByRef m As System.Windows.Forms.Message) As _
  Boolean Implements System.Windows.Forms.IMessageFilter.PreFilterMessage
        If m.Msg = WM_HOTKEY Then
            Select dict(m.WParam)
                Case Keys.Space
                    'ein neues Wort wird begonnen - Prüfen
                    find_badword_arg = actualword
                    Dim pos As Integer = _badwords.FindIndex(AddressOf _
                      find_badword)
                    If pos > -1 Then
                        RaiseEvent BadWordFound(Me, New BadWordsEventArgs( _
                          actualword))
                    End If
                    actualword = ""
                Case Keys.Back
                    'letzte Eingabe rückgängig machen
                Case Else
                    'Alle registrierten Buchstaben sammeln
                    actualword &= dict(m.WParam).ToString
            End Select
 
        End If
        Return True
    End Function

Public Sub New(ByVal OwnerForm As Form)
        mForm = OwnerForm
        Application.AddMessageFilter(Me)
        'Alle Hotkeys registrieren
...
End Sub