private void UpdateDo(DependencyPropertyChangedEventArgs dependencyPropertyChangedEventArgs) { var value = dependencyPropertyChangedEventArgs.NewValue; if (value != null) { AssuranceCompany.DataSource = value; ControlExt.SetDataSource(EntryDate, value); ControlExt.SetDataSource(LeavingDate, value); ControlExt.SetDataSource(Amount, value); ControlExt.SetDataSource(PolizaBox, value); } }