wordpress使用CDN后获取访客真实IP

WordPress使用CDN加速后IP地址不是真实地址，在主题的function.php下添加以下代码即可解决。

/**
 * 获取用户真实IP
 */
function getIP()
{
    static $realIP;
    if (isset($_SERVER)){
        if (isset($_SERVER["HTTP_X_FORWARDED_FOR"])){
            $realIP = explode(',', $_SERVER["HTTP_X_FORWARDED_FOR"]);
	    $realIP = $realIP[0];
        } else if (isset($_SERVER["HTTP_CLIENT_IP"])) {
            $realIP = $_SERVER["HTTP_CLIENT_IP"];
        } else {
            $realIP = $_SERVER["REMOTE_ADDR"];
        }
    } else {
        if (getenv("HTTP_X_FORWARDED_FOR")){
            $realIP = getenv("HTTP_X_FORWARDED_FOR");
        } else if (getenv("HTTP_CLIENT_IP")) {
            $realIP = getenv("HTTP_CLIENT_IP");
        } else {
            $realIP = getenv("REMOTE_ADDR");
        }
    }
    $_SERVER['REMOTE_ADDR'] = $realIP;
    //return $realIP;
}
add_action( 'init', 'getIP' );