[slugify] A simple slugifier in PHP. Makes any string safe for inclusion in filenames / paths, urls, and more!

slugify.php

<?php

/**
 * Normalises and removes any unknown characters from a string, making it safe
 * for use as a filename.
 * @param	string  $string		The string to slugificate.
 * @param	integer $maxlength	The maximum desired length of the resultant string.
 * @return	string				The slugified string.
 */
function slugify($string, $maxlength = 50) {
	return substr(preg_replace([
			'/\s+/',
			'/[^a-z0-9\-_]/'
		], [
			'-',
			''
		],
		strtolower(trim($string))
	), 0, $maxlength);
}