public ActionResult Create(CategoryModel model)
 {
     if (ModelState.IsValid)
     {
         model.Url = model.Url.ReplaceWhiteSpacesWithHyphens().ToLower();
         if (!Context.Categories.Any(c => c.Url.ToLower() == model.Url.ToLower()))
         {
             Category newCategory = new Category
                                        {
                                            CreateDate = DateTime.Now
                                        };
             model.UpdateCategory(newCategory);
             Context.Categories.Add(newCategory);
             Context.SaveChanges();
             return RedirectToAction("AllCategories");
         }
         ModelState.AddModelError("Name", Config.TextErrorMessage);
     }
     return View(model);
 }
        public ActionResult Edit(CategoryModel model, String returnUrl)
        {
            Category oldCategory = Context.Categories.
                        SingleOrDefault(c => c.Id == model.Id);
            if (oldCategory == null)
            {
                return RedirectToRoute("HttpError404");
            }
            if (ModelState.IsValid)
            {
                oldCategory.Name = model.Name;
                oldCategory.IsPublic = model.IsPublic;
                Context.SaveChanges();

                if (Url.IsLocalUrl(returnUrl))
                {
                    return Redirect(returnUrl);
                }
                return RedirectToAction("AllCategories");
            }
            model.Url = oldCategory.Url;
            return View(model);
        }