Convert string into slug with single-hyphen delimiters only
function slug($z){ $z = strtolower($z); $z = preg_replace('/[^a-z0-9 -]+/', '', $z); $z = str_replace(' ', '-', $z); return trim($z, '-');}
First strip unwanted characters
$new_string = preg_replace("/[^a-zA-Z0-9\s]/", "", $string);Then changes spaces for unserscores
$url = preg_replace('/\s/', '-', $new_string);Finally encode it ready for use
$new_url = urlencode($url);
This will do it in a Unix shell (I just tried it on my MacOS):
$ tr -cs A-Za-z '-' < infile.txt > outfile.txtI got the idea from a blog post on More Shell, Less Egg