Public Sub CTRL73_5_Clicked(ByVal sender As Object, ByVal e As ClickedEventArgs)
 
            Dim node_von As XPathNavigator = _
            MainDataSource.CreateNavigator().SelectSingleNode( _
            "/my:meineFelder/my:Datumsdifferenz/my:datum_von", NamespaceManager)
            Dim node_bis As XPathNavigator = MainDataSource.CreateNavigator( _
            ).SelectSingleNode( _
            "/my:meineFelder/my:Datumsdifferenz/my:datum_bis", NamespaceManager)
            Dim node_diff As XPathNavigator = MainDataSource.CreateNavigator( _
            ).SelectSingleNode( _
            "/my:meineFelder/my:Datumsdifferenz/my:differenz_tage", _
            NamespaceManager)
 
 
 
            If node_von.Value.Length > 0 And node_bis.Value.Length > 0 Then
 
                Try
 
 
 
 
                    Dim d_von, d_bis As Date
                    d_von = Convert.ToDateTime(node_von.Value)
                    d_bis = Convert.ToDateTime(node_bis.Value)
                    Dim nDays As Long
 
 
                    Dim xDate As New DateTime(2010, 11, 1) 'Datum festlegen
                    Dim yDate As DateTime = xDate.AddDays(-1)
 
 
                    nDays = d_bis.Subtract(d_von).Days + 1
 
 
 
                    Dim differenz_tage As String
                    differenz_tage = IIf(nDays \ 7 > 0, _
                        nDays - (nDays \ 7) * 2, nDays) - _
                      IIf(Weekday(d_von, vbMonday) - 1 + nDays Mod 7 < 6, 0, _
                    IIf(Weekday(d_von, vbMonday) - 1 + nDays Mod 7 = 6, 1, 2))
 
 
 
                    node_diff.SetValue(differenz_tage)
 
                    If node_diff.MoveToAttribute("nil", "" & _
                      "http://www.w3.org/2001/XMLSchema-instance") Then
                        node_diff.DeleteSelf()
                    End If
 
                Catch ex As Exception
                    'keine Aktion, Berechnung abbrechen
                End Try
 
            End If
 
        End Sub
    End Class
End Namespace

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