代码分享-PHP-获取客户端Ip地址

/**
 * 获取客户端IP地址
*/
function get_client_ip() {
    if (getenv("HTTP_CLIENT_IP") && strcasecmp(getenv("HTTP_CLIENT_IP"), "unknown")) {
        $ip = getenv("HTTP_CLIENT_IP");
    } else if (getenv("HTTP_X_FORWARDED_FOR") && strcasecmp(getenv("HTTP_X_FORWARDED_FOR"), "unknown")) {
        $ip = getenv("HTTP_X_FORWARDED_FOR");
    } else if (getenv("REMOTE_ADDR") && strcasecmp(getenv("REMOTE_ADDR"), "unknown")) {
        $ip = getenv("REMOTE_ADDR");
    } else if (isset($_SERVER["REMOTE_ADDR"]) && $_SERVER["REMOTE_ADDR"] && strcasecmp($_SERVER["REMOTE_ADDR"], "unknown")) {
        $ip = $_SERVER["REMOTE_ADDR"];
    } else {
        $ip = "unknown";
    }

    if (stripos($ip, ',') !== false) {
        list($ip,) = explode(',', $ip);
    }

    return $ip;
}