如何更新 php laravel 中数组的特定索引值？

Question

我正在尝试创建添加到购物车 function，并且产品存储在数组中。 数组是这样的：

array:2 [▼
  0 => array:2 [▼
    "product_id" => "Produk-0036"
    "quantity" => "2"
  ]
  1 => array:2 [▼
    "product_id" => "Produk-0037"
    "quantity" => "3"
  ]
]

我的问题是如果 product_id 已经存在于数组中，如何更新数量？

$get_cart = Cookie::get('user_cart');
if(isset($get_cart)) {
    $cart_array[] = json_decode($get_cart);
}

$cart_array[] = ["product_id" => $request->product_id, "quantity" => $request->quantity];
$cart_json = json_encode($cart_array);
$cart_cookies = Cookie::forever('user_cart', $cart_json);

使用上面的代码将在数组中添加新索引，而不是更新已存在产品的数量

谢谢

Answer 1

我认为您需要在Cookie::forever之前更新产品数量。

你可以参考我的建议：

$cart_array = [
        ["product_id" => "Produk-0036", "quantity" => 2],
        ["product_id" => "Produk-0037", "quantity" => 3],
    ];
    
foreach($cart_array as &$cart)
{
  if(isset($cart["product_id"]) && $cart["product_id"] == $request->product_id) 
  {
      $cart["quantity"] += $request->quantity;
  }
}
$cart_json = json_encode($cart_array);
$cart_cookies = Cookie::forever('user_cart', $cart_json);

Answer 2

您可以使用array_map() function

尝试这样的事情：

$cart_array = [
    [
        "product_id" => "Produk-0036",
        "quantity" => "2"
    ],
    [
        "product_id" => "Produk-0037",
        "quantity" => "3"
    ]
];

$product_id = "Produk-0036";        // product_id to update

$cart_array = array_map(function ($item) use ($product_id) {
    if ($item["product_id"] == $product_id) {
        $item["quantity"] = "5";    // update quantity
    }
    return $item;
}, $cart_array);

var_dump($cart_array); // OUTPUT: updated array