PHP - Trim a string without breaking words

neat_trim($your_text, 100);

function neat_trim( $string, $n, $close = '…' ) {

$len = strlen( $string );

if ($len > $n) {
preg_match('/(.{' . $n . '}.*?)b/', $string, $matches);
return rtrim($matches[1]) . $close;
} else {
return $string;
}

}