用拉拉手推车展示产品

Question

我有laravel 5.5项目，我用session制作了cart系统，调试它时，它很好地工作，并将产品添加到cart中，但是在cart视图中获得具有foreach的产品时，我有问题，下面是错误：

为foreach()提供的无效参数

这是我的刀片代码：

@if (Session::has('cart'))
    @foreach($products as $product)
        {{$product->title}}
    @endforeach
@else
    no product
@endif

这是我的Cart model

public $items;
public $totalQty = 0;
public $totalPrice = 0;

public function __construct($oldCart) {
   if ($oldCart) {
        $this->items = $oldCart->items;
        $this->items = $oldCart->totalQty;
        $this->items = $oldCart->totalPrice;
   }
}

public function add($item, $id) {
   $storedItem = ['qty' => 0, 'price' => $item->price, 'item' => $item];
   if ($this->item) {
        if (array_key_exists($id, $this->items)) {
          $storedItem = $this->items[$id];
        }
   }
   $storedItem['qty']++;
   $storedItem['price'] = $item->price * $storedItem['qty'];
   $this->items[$id] = $storedItem;
   $this->totalQty++;
   $this->totalPrice += $item->price;
}

这是我的CartController

public function AddToCart(Request $request, $id)
{
        $product = Product::find($id);
        $oldCart = Session::has('cart') ? Session::get('cart') : null;
        $cart = new Cart($oldCart);
        $cart->add($product, $product->id);
        $request->session()->put('cart', $cart);
        return redirect()->back();
}

public function index()
{
      if (!Session::has('cart')) {
        return view('frontend.cart');
      }
      $oldCart = Session::get('cart');
      $cart = new Cart($oldCart);
      return view('frontend.cart', ['products' => $cart->items, 'totalPrice' => $cart->totalPrice]);
}

这是我的路线：

//Cart
Route::resource('/cart', 'CartController', ['except' => ['show', 'create']]);

// Session route for add to cart
Route::get('/add-to-cart/{id}', [
  'uses' => 'CartController@AddToCart',
  'as' => 'product.addToCart'
]);

有人知道我的刀片循环有什么问题吗？

Answer 1

似乎出现了以下错误：

public function __construct($oldCart) {
  if ($oldCart) {
    $this->items = $oldCart->items;
    $this->items = $oldCart->totalQty;
    $this->items = $oldCart->totalPrice;
  }
}

看起来，$this->items = $oldCart->totalPrice;是一个浮点值，而不是一个数组。

也许应该是：

public function __construct($oldCart) {
  if ($oldCart) {
    $this->items = $oldCart->items;
    $this->totalQty = $oldCart->totalQty;
    $this->totalPrice = $oldCart->totalPrice;
  }
}