Get the user's real IP address_PHP Tutorial

  
/**
* Get the user’s real IP address
*
* @return string
​*/ 
function real_ip(){ 
    static $realip = NULL; 
  
    if ($realip !== NULL){ 
        return $realip; 
    } 
  
    if (isset($_SERVER)){ 
        if (isset($_SERVER['HTTP_X_FORWARDED_FOR'])){ 
            $arr = explode(',', $_SERVER['HTTP_X_FORWARDED_FOR']); 
            /* 取X-Forwarded-For中第一个非unknown的有效IP字符串 */ 
            foreach ($arr AS $ip){ 
                $ip = trim($ip); 
  
                if ($ip != 'unknown'){ 
                    $realip = $ip; 
  
                    break; 
                } 
            } 
        } 
        elseif (isset($_SERVER['HTTP_CLIENT_IP'])){ 
            $realip = $_SERVER['HTTP_CLIENT_IP']; 
        } 
        else{ 
            if (isset($_SERVER['REMOTE_ADDR'])){ 
                $realip = $_SERVER['REMOTE_ADDR']; 
            } 
            else{ 
                $realip = '0.0.0.0'; 
            } 
        } 
    } 
    else{ 
        if (getenv('HTTP_X_FORWARDED_FOR')){ 
            $realip = getenv('HTTP_X_FORWARDED_FOR'); 
        } 
        elseif (getenv('HTTP_CLIENT_IP')){ 
            $realip = getenv('HTTP_CLIENT_IP'); 
        } 
        else{ 
            $realip = getenv('REMOTE_ADDR'); 
        } 
    } 
  
    preg_match("/[d.]{7,15}/", $realip, $onlineip); 
    $realip = !emptyempty($onlineip[0]) ? $onlineip[0] : '0.0.0.0'; 
  
    return $realip; 
} 
?> 

摘自 chaojie2009的专栏

http://www.bkjia.com/PHPjc/478363.htmlwww.bkjia.comtruehttp://www.bkjia.com/PHPjc/478363.htmlTechArticle?php /*** Get the user's real IP address * * @return string*/ function real_ip(){ static $realip = NULL; if ($realip !== NULL){ return $realip; } if (isset($_SERVER)){ if (isset($_...