public ActionResult Save(int?id, int?CategoryPSN, string CategoryPSNTitle, string CategoryPSN_0) { ViewBag.parenttypes = ListToSelect(ProductCategoryService.GetParentTypes().Select(o => new SelectListItem() { Value = o.CategorySN.ToString(), Text = o.Title }), emptyTitle: "请选择"); var obj = new ProductCategory() { State = 1 }; SelectListItem category = null; if (id.HasValue) { obj = ProductCategoryService.GetObj(id.Value); category = new SelectListItem { Value = obj.CategoryPSN.ToString(), Text = obj.CategoryPSNTitle, Selected = true }; } else if (CategoryPSN.HasValue) { category = new SelectListItem() { Value = CategoryPSN.ToString(), Text = CategoryPSNTitle, Selected = true } } ; ViewBag.category = category; ViewData["SelectPSN"] = CategoryPSN_0; return(View(obj.IsNullThrow())); }