private void btn_delete_Click(object sender, EventArgs e) { bs = new Bestaetigung(this); bs.ShowDialog(); if (tabControl1.SelectedIndex == 0) { if (deleteSelected) { c.deleteTrack(checked_items); UpdateClickbox(); } } else if (tabControl1.SelectedIndex == 1) { if (deleteSelected) { c.deleteWaypoint(checked_waypoints); UpdateClickbox(); } } }