Laravel 5.2 - 通过JSON响应发送对象时的问题

Question

I have my CartController and have a method add() to add an item to the Cart. The idea is to call this method using AJAX and a JSON response is generated after successfully adding the item to the cart.

class CartController extends Controller
{
   public function add(Request $request, $itemid){

    $cart = Auth::user()->cart;
    $item = Item::find($itemid);

    $cart->items()->attach($item);

    return Response::json([
     'success' => true,
     'cart' => $cart
    ]);
   }
}

My Cart-Items has a many-to-many relationship while my User-Cart has a one-to-one relationship.

When I add the first item to the cart the database updates correctly but my $cart in the response does not contain the item details. The item array under cart is empty, rather the relationship is not being loaded. What do i seem to be doing wrong?

Answer 1

To make sure the json response has the cart items, you should eager load these items. This can be done using the load function.

$cart = Auth::user()->cart;
$item = Item::find($itemid);

$cart->items()->attach($item);

// Reload items
$cart->load('items');

return Response::json([
    'success' => true,
    'cart' => $cart
]);