Laravel 和 Rails 商品展示页面实现对比 - 如何判断商品是否上架

{"title":"public function show(Product $product, Request $request)\n {\n // 判断商品是否已经上架，如果没有上架则抛出异常。\n if (!$product->on_sale) {\n throw new InvalidRequestException('商品未上架');\n }\n\n return view('products.show', ['product' => $product]);\n }\n改写成 rails内容：def show\n product = Product.find(params[:id])\n \n # 判断商品是否已经上架，如果没有上架则抛出异常。\n unless product.on_sale\n raise InvalidRequestException.new('商品未上架')\n end\n \n render 'products/show', locals: { product: product }\nend"}