private void btnAddSubUnit_Click(object sender, RoutedEventArgs e) { if (lbBattalion.SelectedItem != null) { int idFKSubUnit = (lbBattalion.SelectedItem as SubUnit).Id; SubUnit s = addSubUnit.getNewSubUnit(-1, idFKSubUnit); if (s != null) { if (sList == null) { sList = new SubUnitList(); } int id = sqlWorker.getNewId("SubUnit"); s.Id = id; if (sqlWorker.addSubUnit(id, s)) { sList.values.Add(s); } else { MessageBox.Show("Ошибка при добавлении элемента"); } } } }