Php Smarty动态选择字段中的对象

我想创建一个选择下拉列表，其中填充了我放在数组中的Categories数组

$contents

是一个数组，其条目在smarty中自动分配

foreach ($contents as $key => $value) {
    $this->_smarty->assign($key, $value);
}

Controller.php:

private $contents;

public function createStart() {
    $categories = $service->listCategories();
    $this->contents['categories'] = $categories;

    return 'documentsform-view';
}

<select>
  {html_options options=$categories}
</select>

html视图：

private $contents;

public function createStart() {
    $categories = $service->listCategories();
    $this->contents['categories'] = $categories;

    return 'documentsform-view';
}

<select>
  {html_options options=$categories}
</select>

{html_options options=$categories}

这不管用

---

类别是对象。我希望我的选项值采用每个类别ID，并显示每个类别名称。我该怎么做

我用smarty

foreach解决了问题

：

<select>
  {foreach item=category from=$categories}
    {html_options values=$category->getId() output=$category->getName()}
  {/foreach}
</select>

{foreach item=category from=$categories}
{html_options values=$category->getId（）输出=$category->getName（）}
{/foreach}