public async Task <ActionResult> EditMajor(MajorEditViewModel model)
        {
            if (ModelState.IsValid)
            {
                var major = await InstitutionManager.FindMajorByIdAsync(model.Id);

                if (major == null)
                {
                    ModelState.AddModelError("", "未找到此项major");
                    return(View(model));
                }
                var depart = await InstitutionManager.FindDepartmentByIdAsync(model.DepartmentId);

                if (depart == null)
                {
                    ModelState.AddModelError("", "未找到此项depart");
                    return(View(model));
                }
                major.Name       = model.MajorName;
                major.Department = depart;
                await InstitutionManager.UpdateMajorAsync(major);

                return(RedirectToAction("AllMajor"));
            }
            return(View(model));
        }