如何从没有变量的url获取变量

I am trying to GET the int from the following string

member.php?3-bradthor

I have tried using the following code

    $query = parse_url($str, PHP_URL_QUERY);
$intval = preg_replace("/[^0-9]/","",' $query');

However I don't think this is a fool proof solution? what Imporovements could I make to this code/what code should I use to get the integer from the above string. Thanks for the help :)

Check this,

$str = 'member.php?3-bradthor';
$query = parse_url($str, PHP_URL_QUERY);

$intval = preg_replace("/[^0-9]/","",$query);// remove single quotes.

echo $intval;

Working demo

Because of how integers are parsed in PHP you can simple use

$query = parse_url('member.php?3-bradthor', PHP_URL_QUERY);
$intval = intval($query);

if will work only when number in the begining of string.

Less dirty solution is to use for example mod_rewrite.