$userIp = $_SERVER['REMOTE_ADDR']; echo "Your IP address is: " . $userIp;
$userIp = $_SERVER['REMOTE_ADDR']; mysqli_query("INSERT INTO users (ip_address) VALUES ('$userIp')");
$userIp = $_SERVER['REMOTE_ADDR']; if (preg_match('/^(?:[0-9]{1,3}\.){3}[0-9]{1,3}$/', $userIp)) { echo "Valid IP address"; } else { echo "Invalid IP address"; }Package: No package library required as this is a built-in function in PHP.