public ActionResult RemoveFromRelation(AddStuOrTe Aso)
        {
            string[] ids     = Aso.Ids.Split(new char[] { '|' });
            string   subType = "";

            if (Aso.userType == "教师")
            {
                subType = "学生";
                RemoveStudents(Aso.Id, ids);
            }
            else if (Aso.userType == "学生")
            {
                subType = "教师";
                RemoveMentor(Aso.Id, ids);
            }
            return(RedirectToAction("stuOrTeachers", new { Id = Aso.Id, userType = Aso.userType, subType = subType }));
        }
        public ActionResult AddStuOrTe(AddStuOrTe Aso)
        {
            string[] ids      = Aso.Ids.Split(new char[] { '|' });
            string   userType = "";

            if (Aso.userType == ("教师"))
            {
                userType = "学生";
                AddMentors(Aso.Id, ids);
            }
            else if (Aso.userType == ("学生"))
            {
                userType = "教师";
                AddStudents(Aso.Id, ids);
            }
            return(RedirectToAction("stuOrTeachers", new { Id = Aso.Id, userType = userType, subType = Aso.userType }));
        }