Private Sub elapsetimer_Tick(sender As Object, _
                e As System.EventArgs) Handles elapsetimer.Tick
 
     lblElapsed.Text = String.Empty
 
     With timetable
        For i As Integer = 0 To .Rows.Count - 1
           'Laufende Zeitmessung
           If IsDBNull(.Rows(i)("Ende")) Then
 
              'Seit dem Start verstrichene Sekunden in Intervall-Spalte 
              ' eintragen
              Dim start As Date = DirectCast(.Rows(i)("Start"), Date)
              Dim elapsed As New TimeSpan(Now.Ticks - start.Ticks)
 
              .Rows(i)("Intervall") = elapsed.TotalSeconds
 
              'aktuell angezeigtes Projekt in Projektgrid
              Dim row As DataRow = DirectCast(bs(bs.Position), DataRowView).Row
              Dim projectid As Integer
              If Not Integer.TryParse(row.Item("ID").ToString, projectid) Then _
                Exit Sub
 
              If CInt(.Rows(i)("ProjectId").ToString) = projectid Then
                  lblElapsed.Text = _
                  "Projekt-ID (" & .Rows(i)("ProjectID").ToString & "): " & _
                  elapsed.ToString("g")
              End If
 
           End If
        Next i
     End With
End Sub