如何在PHP中拆分中文字符？

<?php
$string = "你好，世界！";
$char_length = mb_strlen($string, 'UTF-8');

for ($i = 0; $i < $char_length; $i++) {
    $char = mb_substr($string, $i, 1, 'UTF-8');
    echo $char . PHP_EOL;
}
?>