public ActionResult Edit(ProductPropertyManageEditViewModel model)
        {
            if (ModelState.IsValid)
            {
                string newPropertymgUrl;
                if (model.PropertyImg != null)
                {
                    var uploadedFile = new UploadedFile(model.PropertyImg);
                    var propertyImgName = uploadedFile.SaveAs(Server.MapPath("~/ImgRepository/ProductPropertyImgs/"));

                    var pathRel = Url.Content("~/ImgRepository/ProductPropertyImgs/" + propertyImgName);
                    newPropertymgUrl = pathRel;
                }
                else
                {
                    newPropertymgUrl = db.Products.Find(model.Id).CoverImgUrl;
                }

                var productProperty = new ProductProperty
                {
                    Id=model.Id,
                    Name=model.Name,
                    Description=model.Description,
                    ImgUrl= newPropertymgUrl,
                    PlusPrice=model.PlusPrice
                };
                db.Entry(productProperty).State = EntityState.Modified;
                db.SaveChanges();
                return RedirectToAction("Index");
            }
            return View(model);
        }
        // GET: ProductPropertyManage/Edit/5
        public ActionResult Edit(int? id)
        {
            if (id == null)
            {
                return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
            }
            ProductProperty productProperty = db.ProductProperties.Find(id);
            if (productProperty == null)
            {
                return HttpNotFound();
            }

            var vm = new ProductPropertyManageEditViewModel
            {
                Id=productProperty.Id,
                Name=productProperty.Name,
                Description=productProperty.Description,
                ImgUrl=productProperty.ImgUrl,
                PlusPrice=productProperty.PlusPrice
            };
            return View(vm);
        }