private void delete_button_Click(object sender, RoutedEventArgs e) { if (deleteCB.SelectedItem == null) { MessageBox.Show("Please select an item to delete."); } else { oldCourse = student.CourseList[deleteCB.SelectedIndex]; student.DeleteCourse(deleteCB.SelectedIndex); FileReadWrite file = new FileReadWrite(); file.DeleteCourseToFile(student, oldCourse); ViewCourses vc = new ViewCourses(student); this.Close(); vc.Show(); } }