Generate clean URL (slug) from a string

slugify.php

<?php
/**
 * Generates clean URL
 * 
 * @param  string
 * @return string
 */
function slugify( $string ) {
	$cleanString = preg_replace( "/[^a-zA-Z0-9\/_|+ -]/", '', $string );
	$cleanString = strtolower( trim( $cleanString, '-' ) );
	$cleanString = preg_replace( "/[\/_|+ -]+/", '-', $cleanString );

	return $cleanString;
}