php获取当前访问者ip

<?php
function getVisitorIP() {
    if (!empty($_SERVER['HTTP_CLIENT_IP'])) {
        $ip = $_SERVER['HTTP_CLIENT_IP'];
    } elseif (!empty($_SERVER['HTTP_X_FORWARDED_FOR'])) {
        $ip = $_SERVER['HTTP_X_FORWARDED_FOR'];
    } else {
        $ip = $_SERVER['REMOTE_ADDR'];
    }
    return $ip;
}

$visitorIP = getVisitorIP();
echo "Visitor IP: " . $visitorIP;
?>

<?php
function getVisitorIP() {
    if (getenv('HTTP_CLIENT_IP')) {
        $ip = getenv('HTTP_CLIENT_IP');
    } elseif (getenv('HTTP_X_FORWARDED_FOR')) {
        $ip = getenv('HTTP_X_FORWARDED_for');
    } else {
        $ip = getenv('REMOTE_ADDR');
    }
    return $ip;
}

$visitorIP = getVisitorIP();
echo "Visitor IP: " . $visitorIP;
?>