public ActionResult EditClass(Models.View_TeacherClasses tc)
        {
            try
            {
                var c    = tdb.Classes.Single(t => t.ID == tc.ID);
                var ttcc = tdb.TeacherClasses.Where(t => t.ClassID == tc.ID);
                if (ttcc.Count() == 0)
                {
                    tdb.TeacherClasses.Add(new Models.TeacherClasses()
                    {
                        TeacherID = tc.TeacherID, ClassID = tc.ID, Status = 0
                    });
                }
                else
                {
                    var teaclass = ttcc.ToList()[0];
                    teaclass.TeacherID = tc.TeacherID;
                    teaclass.Status    = 0;
                    teaclass.ClassID   = tc.ID;
                }
                c.Name = tc.Name;

                tdb.SaveChanges();
                return(Content("ok"));
            }
            catch
            {
                return(Content("err"));
            }
        }
 public ActionResult AddClass(Models.View_TeacherClasses classteacher)
 {
     try
     {
         tdb.AddClasses(classteacher.MajorID, classteacher.Name, classteacher.TeacherID);
         return(Content("ok"));
     }
     catch
     {
         return(Content("err"));
     }
 }