php - 为什么使用 unset() 函数将数组转换为对象？

Question

这是我的代码:

return ApiResponse::Json(200, '', ['categories' => $categories], 200);

这是结果的屏幕截图:

现在，我需要取消设置 categories 中的项目基于特定逻辑的集合。所以我写了这个循环:

foreach ($categories as $key => $category) {
    if ($category->BusinessSubCategory->isEmpty())
          unset($categories[0]);
}

return ApiResponse::Json(200, '', ['categories' => $categories], 200);

这是我的新结果:(被转换为一个对象)

嗯.. 怎么了？取消设置某些项目后如何保留旧结构？

Answer 1

尝试这个:

foreach ($categories as $key => $category) {
    if ($category->BusinessSubCategory->isEmpty())
          unset($categories[$key]);

}

$categories = array_slice($categories->toArray(), 0, count($categories));

return ApiResponse::Json(200, '', ['categories' => $categories], 200);