OpenCart中Twig模板遍历对象数组失效问题求助

在OpenCart开发中，控制器整理好分类-商品结构的数组后，误将其转为JSON字符串传递给Twig视图，导致视图中无法用{% for %}遍历，直接输出显示为纯文本。

控制器错误代码 #

$data['crackers'] = [];
$results = $this->model_quickorder_order->getCrackers();

$categories = [];
foreach ($results as $row) {
    $categoryId = $row['category_id'];
    $categoryName = $row['category_name'];
    $productId = $row['product_id'];
    $productName = $row['name'];
    $specialPrice = $row['special'];
    $productPrice = $row['price'];
    $productImage = $row['product_image'];

    $product = [
        'product_id' => $productId,
        'product_name' => $productName,
        'special_price' => $specialPrice,
        'price' => $productPrice,
        'product_image' => $productImage,
    ];

    if (!isset($categories[$categoryId])) {
        $categories[$categoryId] = [
            'category_id' => $categoryId,
            'category_name' => $categoryName,
            'products' => [], // 初始化该分类下的商品数组
        ];
    }

    $categories[$categoryId]['products'][] = $product;
}

$categoriesArray = array_values($categories);
$jsonCategories = json_encode($categoriesArray, JSON_PRETTY_PRINT);
$data['crackers'] = $jsonCategories;
echo $data['crackers'];

视图输出代码（直接显示文本） #

{{ crackers }}

输出结果 #

[ { "category_id": "67", "category_name": "Flower Pots", "products": [ { "product_id": "1", "product_name": "Flower Pots Small (10Pcs)", "special_price": "110.0000", "price": "220.0000", "product_image": "catalog/flowerpotssmall.jpg" } ] }, { "category_id": "69", "category_name": "Chakkars", "products": [ { "product_id": "2", "product_name": "Zamin Chakkar Ashoka (10 pcs)", "special_price": "150.0000", "price": "300.0000", "product_image": "catalog/Zamin_Chakkar_Asoka.jpg" } ] } ]

无法正常执行的遍历代码 #

{% for cracker in crackers %}
  <tr class='heading'>
    <td colspan="5"> {{ cracker.name }}</td>
  </tr>
 </td>
</tbody>
</tr>
 {% endfor %}

方法1：修正控制器代码（推荐） #

直接传递PHP数组给视图，无需转为JSON字符串。删除控制器中json_encode相关代码，把整理好的数组直接赋值给$data['crackers']：

$data['crackers'] = [];
$results = $this->model_quickorder_order->getCrackers();

$categories = [];
foreach ($results as $row) {
    $categoryId = $row['category_id'];
    $categoryName = $row['category_name'];
    $productId = $row['product_id'];
    $productName = $row['name'];
    $specialPrice = $row['special'];
    $productPrice = $row['price'];
    $productImage = $row['product_image'];

    $product = [
        'product_id' => $productId,
        'product_name' => $productName,
        'special_price' => $specialPrice,
        'price' => $productPrice,
        'product_image' => $productImage,
    ];

    if (!isset($categories[$categoryId])) {
        $categories[$categoryId] = [
            'category_id' => $categoryId,
            'category_name' => $categoryName,
            'products' => [], // 初始化该分类下的商品数组
        ];
    }

    $categories[$categoryId]['products'][] = $product;
}

// 直接传递数组，不要转JSON
$data['crackers'] = array_values($categories);
// 移除echo语句，避免提前输出内容干扰视图渲染
// echo $data['crackers'];

方法2：在Twig视图中解析JSON（不推荐） #

如果无法修改控制器，可在Twig中使用json_decode过滤器将字符串转回数组，同时修正字段名错误：

{% set crackers_array = crackers|json_decode %}
{% for cracker in crackers_array %}
  <tr class='heading'>
    <td colspan="5">{{ cracker.category_name }}</td>
  </tr>
  {# 遍历分类下的商品 #}
  {% for product in cracker.products %}
    <tr>
      <td>{{ product.product_name }}</td>
      <td>{{ product.price }}</td>
      <td>{{ product.special_price }}</td>
    </tr>
  {% endfor %}
{% endfor %}

关键注意点 #

• 遍历代码中字段名要匹配原数据：分类名称是category_name，不是cracker.name，需修正。
• 控制器中必须移除echo $data['crackers'];，否则会提前输出JSON内容，破坏视图的HTML结构。

内容的提问来源于stack exchange，提问作者Maria Jeysingh Anbu