private void Button_Click(object sender, RoutedEventArgs e) { if ((int)cmbNodeList.SelectedValue < 0) { return; } gui.DisconnectHyperArcConnection(firstHyperArc, firstHyperArc.nodes[(int)cmbNodeList.SelectedValue]); UpdateDisconnectComboBox(sender, null); cmbNodeList.SelectedIndex = 0; }