CodeIgniter Helper - Friendly URL

friendlyurl_helper.php

<?php 
function friendlyURL($string, $is_file = false, $delimiter = '-'){
	if ($is_file) {
		$name = pathinfo($string, PATHINFO_FILENAME);
		$ext = pathinfo($string, PATHINFO_EXTENSION);
		$filename = friendlyUrl($name) . '.' . friendlyUrl($ext);
		return $filename;
	} else {
		$string = preg_replace("`\[.*\]`U","",$string);
		$string = preg_replace('`&(amp;)?#?[a-z0-9]+;`i', $delimiter, $string);
		$string = htmlentities($string, ENT_COMPAT, 'utf-8');
		$string = preg_replace( "`&([a-z])(acute|uml|circ|grave|ring|cedil|slash|tilde|caron|lig|quot|rsquo);`i","\\1", $string );
		$string = preg_replace( array("`[^a-z0-9]`i","`[-]+`") , $delimiter, $string);
	}
	return strtolower(trim($string));
}
?>