如何将PHP中的字符串截断为最接近一定数量字符的单词？

function truncateString($string, $maxLength) {
    if (strlen($string) <= $maxLength) {
        return $string;
    }

    $truncated = substr($string, 0, $maxLength);

    $lastSpacePosition = strrpos($truncated, ' ');
    if ($lastSpacePosition !== false) {
        $truncated = substr($truncated, 0, $lastSpacePosition);
    }

    $truncated .= '...';

    return $truncated;
}

$string = "Hello, this is a long sentence that needs to be truncated.";
$maxLength = 20;
$truncatedString = truncateString($string, $maxLength);
echo $truncatedString;

Hello, this is a...