public ActionResult RemoveSubjects(SubjectViewModel model)
        {
            foreach (var subject in model.Subjects)
            {
                if (subject.Value == true)
                {
                    _semesterSubjectService.DeleteSubjectAndSave(subject.Key);
                }
            }
            model = new SubjectViewModel(_semesterSubjectService.GetAllSubjects().OrderBy(s => s.Name).ToList());

            return PartialView("~/Views/Partials/Management/ManageSubjects.cshtml", model);
        }
        public ActionResult ManageSubjectsList()
        {
            var subjectList = _semesterSubjectService.GetAllSubjects().OrderBy(s => s.Name).ToList();
            SubjectViewModel model = new SubjectViewModel(subjectList);

            return PartialView("~/Views/Partials/Management/ManageSubjects.cshtml", model);
        }
        public ActionResult RemoveSubject(string subjectName)
        {
            if (!subjectName.IsEmpty())
            {
                _semesterSubjectService.DeleteSubjectAndSave(subjectName);
            }

            SubjectViewModel model = new SubjectViewModel(_semesterSubjectService.GetAllSubjects().OrderBy(s => s.Name).ToList());

            return PartialView("~/Views/Partials/Management/ManageSubjects.cshtml", model);
        }
        public ActionResult AddSubject(string subjectName)
        {
            if (subjectName != "")
            {
                _semesterSubjectService.AddAndSaveSubject(subjectName);
            }

            var subjectList = _semesterSubjectService.GetAllSubjects().OrderBy(s => s.Name).ToList();
            SubjectViewModel model = new SubjectViewModel(subjectList);

            return PartialView("~/Views/Partials/Management/ManageSubjects.cshtml", model);
        }