public ActionResult Save(Student student)
        {
            if (!ModelState.IsValid)
            {
                var cohorts   = _context.Cohorts.ToList();
                var viewModel = new CohortsForSingleStudentViewModel
                {
                    CohortTypes = cohorts,
                    Student     = student
                };
                return(View("StudentForm", viewModel));
            }

            if (student.Id == 0)
            {
                _context.Students.Add(student);
            }
            else
            {
                var studentInDb = _context.Students.Single(s => s.Id == student.Id);
                studentInDb.Name         = student.Name;
                studentInDb.CohortTypeId = student.CohortTypeId;
            }

            _context.SaveChanges();

            return(RedirectToAction("Index", "Student"));
        }
        public ActionResult New()
        {
            var cohorts   = _context.Cohorts.ToList();
            var viewModel = new CohortsForSingleStudentViewModel
            {
                CohortTypes = cohorts,
                Student     = new Student()
            };

            return(View("StudentForm", viewModel));
        }
        public ActionResult Edit(int id)
        {
            var cohorts = _context.Cohorts.ToList();
            var student = _context.Students.SingleOrDefault(s => s.Id == id);

            if (student == null)
            {
                return(HttpNotFound());
            }
            var viewModel = new CohortsForSingleStudentViewModel
            {
                CohortTypes = cohorts,
                Student     = student
            };

            return(View("StudentForm", viewModel));
        }