private void listBox_lv2_SelectedIndexChanged(object sender, EventArgs e) { if (listBox_lv1.SelectedIndex != -1 && listBox_lv2.SelectedIndex != -1) { consMgr.setExamLv3(listBox_lv3, int.Parse(((PermissibleValueObj)(listBox_lv1.SelectedItem)).Value), int.Parse(((PermissibleValueObj)(listBox_lv2.SelectedItem)).Value)); if (listBox_lv3.Items.Count == 1) { listBox_lv3.SelectedIndex = 0; } } }