private void cbCourses_SelectedIndexChanged(object sender, EventArgs e) { // if choise course name if (cbCourses.SelectedIndex > 0) { string courseName = cbCourses.SelectedItem.ToString(); // open new form with parametrs and get answer if any change SeatPlan seatPlan = new SeatPlan(courses, courseName); if (seatPlan.ShowDialog() == DialogResult.OK) { //Debug.WriteLine(seatPlan.Change.ToString()); // any changes change = change || seatPlan.Change; cbCourses.SelectedIndex = 0; } } }