<Extension()> _
      Public Function FindX(ByVal bs As BindingSource, ByVal columnName As _
      String, ByVal Key As Object) As Integer
         'BindingSource.Find funzt nicht bei relateten BindingSourcses
         'FindX = bs.Find(columnName, Key)
         For i As Integer = 0 To bs.Count - 1
            If DirectCast(bs(i), DataRowView)(columnName).Equals(Key) Then _
              Return i
         Next
         Return -1
      End Function

(Rechtschreibfehler urheberrechtlich geschützt)