tryphp_filter5.php:
<!DOCTYPE html> <html> <body> <?php $ip = "127.0.0.1"; if (!filter_var($ip, FILTER_VALIDATE_IP) === false) { echo("$ip is a valid IP address"); } else { echo("$ip is not a valid IP address"); } ?> </body> </html>
127.0.0.1 is a valid IP address