public static void DeleteSubject(int id)
{
List <Grade> grades = GradeManager.GetGradesBySubject(id);
foreach (Grade grade in grades)
{
GradeManager.DeleteGrade(grade.id);
}
List <Lesson> lessons = LessonManager.GetLessonsBySubject(id);
foreach (Lesson lesson in lessons)
{
LessonManager.DeleteLesson(lesson.day, lesson.lesson_time);
}
MyData.my_subjects_list.Remove(MyData.my_subjects_list.Find(x => x.id == id));
}
public void DeleteGrade()
{
GradeManager.DeleteGrade(this.id);
}
