//add manytomany to db
public static CourseTeacher BindTeacherToCourse(int teacherId, int courseId)
{
CoursesEntities db = new CoursesEntities();
if (db.CourseTeachers.Where(p => p.TeacherId == teacherId && p.CourseId == courseId).Count() != 0)
{
return(null);
}
CourseTeacher newCourseTeacher = new CourseTeacher();
newCourseTeacher.CourseId = courseId;
newCourseTeacher.TeacherId = teacherId;
db.CourseTeachers.Add(newCourseTeacher);
try
{
db.SaveChanges();
db.Dispose();
}
catch (System.Data.Entity.Validation.DbEntityValidationException)
{
db.Dispose();
return(null);
}
return(newCourseTeacher);
}
//delete manytomany from db
public static bool DelBindTeacherToCourse(int id)
{
CoursesEntities db = new CoursesEntities();
CourseTeacher courseTeacher = db.CourseTeachers.Find(id);
if (courseTeacher != null)
{
db.CourseTeachers.Remove(courseTeacher);
try
{
db.SaveChanges();
db.Dispose();
return(true);
}
catch (Exception)
{
db.Dispose();
return(false);
}
}
return(false);
}