public ActionResult Create(StudyInformation studyinformation)
        {
            if (ModelState.IsValid)
            {
                db.StudyInfos.Add(studyinformation);
                db.Commit();
                return RedirectToAction("Index");
            }

            // ViewBag.StudyId = new SelectList(db.Studies, "Id", "Name", studyinformation.StudyId);
            ViewBag.StudyId = new SelectList(db.Studies.GetAll(), "Id", "Name", studyinformation.StudyId);
            return View(studyinformation);
        }
        public ActionResult Edit(StudyInformation studyinformation)
        {
            if (ModelState.IsValid)
            {
                db.StudyInfos.GetById(studyinformation.Id).Study = studyinformation.Study;
                db.StudyInfos.GetById(studyinformation.Id).Content = studyinformation.Content;
                db.StudyInfos.GetById(studyinformation.Id).StudyId = studyinformation.StudyId;
                db.StudyInfos.GetById(studyinformation.Id).Title = studyinformation.Title;
                db.StudyInfos.GetById(studyinformation.Id).Study = studyinformation.Study;

                // db.Entry(studyinformation).State = EntityState.Modified;
                db.Commit();
                return RedirectToAction("Index");
            }
            ViewBag.StudyId = new SelectList(db.Studies.GetAll(), "Id", "Name", studyinformation.StudyId);
            return View(studyinformation);
        }