public ActionResult Create(Course course)
        {
            if (ModelState.IsValid)
            {
                db.Courses.Add(course);
                db.SaveChanges();
                return RedirectToAction("Index");
            }

            return View(course);
        }
 public ActionResult Edit(Course course)
 {
     if (ModelState.IsValid)
     {
         db.Entry(course).State = EntityState.Modified;
         db.SaveChanges();
         return RedirectToAction("Index");
     }
     return View(course);
 }
        // PUT api/Course/5
        public HttpResponseMessage PutCourse(string id, Course course)
        {
            if (!ModelState.IsValid)
            {
                return Request.CreateErrorResponse(HttpStatusCode.BadRequest, ModelState);
            }

            if (id != course.courseId)
            {
                return Request.CreateResponse(HttpStatusCode.BadRequest);
            }

            db.Entry(course).State = EntityState.Modified;

            try
            {
                db.SaveChanges();
            }
            catch (DbUpdateConcurrencyException ex)
            {
                return Request.CreateErrorResponse(HttpStatusCode.NotFound, ex);
            }

            return Request.CreateResponse(HttpStatusCode.OK);
        }
        // POST api/Course
        public HttpResponseMessage PostCourse(Course course)
        {
            if (ModelState.IsValid)
            {
                db.Courses.Add(course);
                db.SaveChanges();

                HttpResponseMessage response = Request.CreateResponse(HttpStatusCode.Created, course);
                response.Headers.Location = new Uri(Url.Link("DefaultApi", new { id = course.courseId }));
                return response;
            }
            else
            {
                return Request.CreateErrorResponse(HttpStatusCode.BadRequest, ModelState);
            }
        }