php 如何把对象转换成数组对象

/**
 * 数组 转 对象
 *
 * @param array $arr 数组
 * @return object
 */
function array_to_object($arr) {
    if (gettype($arr) != 'array') {
        return;
    }
    foreach ($arr as $k => $v) {
        if (gettype($v) == 'array' || getType($v) == 'object') {
            $arr[$k] = (object)array_to_object($v);
        }
    }
 
    return (object)$arr;
}
 
/**
 * 对象 转 数组
 *
 * @param object $obj 对象
 * @return array
 */
function object_to_array($obj) {
    $obj = (array)$obj;
    foreach ($obj as $k => $v) {
        if (gettype($v) == 'resource') {
            return;
        }
        if (gettype($v) == 'object' || gettype($v) == 'array') {
            $obj[$k] = (array)object_to_array($v);
        }
    }
 
    return $obj;
}