public ActionResult Create(CatalogModel catalogmodel)
        {
            if (ModelState.IsValid)
            {
                db.Catalogs.Add(catalogmodel);
                catalogmodel.CreateTime = DateTime.Now;
                db.SaveChanges();

                return RedirectToAction("Index");
            }

            return View(catalogmodel);
        }
 public ActionResult Edit(CatalogModel catalogmodel)
 {
     if (ModelState.IsValid)
     {
         db.Entry(catalogmodel).State = EntityState.Modified;
         db.SaveChanges();
         return RedirectToAction("Index");
     }
     return View(catalogmodel);
 }