如何使用 php 将多个对象数组写入 json 文件

因为您正在循环中写入文件，所以每次都会覆盖其内容.

要将所有数据写入一个文件，并使其写入一个有效的JSON实体，该实体稍后将再次可解码，您需要构建一个包含所有产品数据的单个数组，然后在循环结束后对该数组进行编码并将其写入文件一次.

例如:

$products = array();

foreach($crawler as $node)
{
    $title = $node->filter('h3')->text();
    $img = $node->filter('img')->attr('src');
    $color = $node->filter('div.my-4 div.flex div.px-2 span')->attr('data-colour');
    $capacity = $node->filter('span.product-capacity')->text();
    $availibity = $node->filter('div.text-sm')->text();
    $shippingText = $node->filter('div.bg-white > div')->last()->text();
    $shippingDate = $node->filter('div.bg-white > div')->last()->text();
    
    $productArray = array (
          'title' => $title,
          'price' => 12,
          'imageUrl'=> 'https://www.magpiehq.com/developer-challenge/smartphones/'.$img,
          'capacityMB' => $capacity,
          'colour' => $color,
          'availabilityText' => $availibity,
          'shippingText' =>$shippingText,
          'shippingDate' =>$shippingDate
    );
    
    $products[] = $productArray; //add the current item to the overall array
}

//encode all the data at once, and then write it to the file
$json = json_encode($products);
file_put_contents("output.json", $json);