PHP：如何将多维数组转回含stdClass Object的数组？

场景还原 #

初始结构：包含stdClass Object的数组

Array
(
    [0] => stdClass Object
        (
            [ID] => 5384
            [post_title] => Accordeon me con jQuery
            [post_name] => accordeon-con-jquery
            [readings] => 55140
            [post_date] => 01-12-2012
            [media] => 59.546436285097
            [dias] => 926
        )
 
    [1] => stdClass Object
        (
            [ID] => 2509
            [post_title] => Popup me con jQuery
            [post_name] => popup-me-con-jquery
            [readings] => 26261
            [post_date] => 13-04-2012
            [media] => 22.677892918826
            [dias] => 1158
        )
        ...

将其转为多维数组的代码：

$visits = json_decode(json_encode($visits), true);

转换后得到符合预期的多维数组：

Array
(
    [0] => Array
        (
            [ID] => 5384
            [post_title] => Accordeon me con jQuery
            [post_name] => accordeon-con-jquery
            [readings] => 55140
            [post_date] => 01-12-2012
            [media] => 59.546436285097
            [dias] => 926
        )
 
    [1] => Array
        (
            [ID] => 2509
            [post_title] => Popup me con jQuery
            [post_name] => popup-me-con-jquery
            [readings] => 26261
            [post_date] => 13-04-2012
            [media] => 22.677892918826
            [dias] => 1158
        )
        ...

尝试转回时使用以下代码，得到意外结果（外层为stdClass Object）：

$visits = json_decode(json_encode($visits));

意外结果：

stdClass Object
(
    [0] => stdClass Object
        (
            [ID] => 5384
            [post_title] => Accordeon me con jQuery
            [post_name] => accordeon-con-jquery
            [readings] => 55140
            [post_date] => 01-12-2012
            [media] => 59.546436285097
            [dias] => 926
        )
 
    [1] => stdClass Object
        (
            [ID] => 2509
            [post_title] => Popup me con jQuery
            [post_name] => popup-me-con-jquery
            [readings] => 26261
            [post_date] => 13-04-2012
            [media] => 22.677892918826
            [dias] => 1158
        )
        ...

解决方案 #

方法1：使用array_map遍历转换 #

通过array_map将数组中的每个子数组转为stdClass对象，外层保持数组结构：

$visits = array_map(function($item) {
    return (object)$item;
}, $visits);

方法2：重置数组索引后再用JSON转换 #

如果原多维数组的索引不连续（存在间隙或非数字键），json_encode会将其转为JSON对象，导致json_decode返回外层为stdClass。此时可先用array_values重置索引为连续数字，再进行转换：

$visits = json_decode(json_encode(array_values($visits)));

方法3：手动foreach遍历转换 #

手动遍历数组，将每个子数组转为stdClass并添加到新数组中：

$newVisits = [];
foreach ($visits as $item) {
    $newVisits[] = (object)$item;
}
$visits = $newVisits;

内容的提问来源于stack exchange，提问作者plasticheart