private void lstSessions_SelectedIndexChanged(object sender, EventArgs e) { if (lstSessions.SelectedIndex == -1) { ClearForm.Clear(this); } else if (lstSessions.SelectedIndex > -1) { Session session = (Session)lstSessions.SelectedItem; dtpSessionDate.Value = session.Date + session.Time; cmbMovies.SelectedValue = session.Movie.ID; cmbTheatres.SelectedValue = session.MovieTheatre.MovieTheatreID; lstTickets.DataSource = null; lstTickets.DataSource = TicketDataTransaction.GetTicketDetail(session); } }