function which will remove all but leave only numbers for php:
p.s. If you are looking for function to delete all except chars and numbers look here:
http://pilotaz.blogspot.com/2011/08/php-string-replace-all-except-numbers.html
$string = preg_replace('#[^0-9]#','',strip_tags($string));
p.s. If you are looking for function to delete all except chars and numbers look here:
http://pilotaz.blogspot.com/2011/08/php-string-replace-all-except-numbers.html