php获取客户端真实ip地址的三种方法

php获取用户(客户端)真实IP地址的三种方法

第一种方法,还算靠谱,本人以前一直用的是这个方法:

function get_real_ip(){ 
    $ip=false; 
    if(!empty($_SERVER['HTTP_CLIENT_IP'])){ 
        $ip=$_SERVER['HTTP_CLIENT_IP']; 
    }
    if(!empty($_SERVER['HTTP_X_FORWARDED_FOR'])){ 
        $ips=explode (', ', $_SERVER['HTTP_X_FORWARDED_FOR']); 
        if($ip){ array_unshift($ips, $ip); $ip=FALSE; }
        for ($i=0; $i < count($ips); $i++){
            if(!eregi ('^(10│172.16│192.168).', $ips[$i])){
                $ip=$ips[$i];
                break;
            }
        }
    }
    return ($ip ? $ip : $_SERVER['REMOTE_ADDR']); 
}

第二种方法:

function get_real_ip(){
    static $realip;
    if(isset($_SERVER)){
        if(isset($_SERVER['HTTP_X_FORWARDED_FOR'])){
            $realip=$_SERVER['HTTP_X_FORWARDED_FOR'];
        }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');
        }
    }
    return $realip;
}

第三种方法,摘自DISCUZ,应该还不错吧!

// 获取IP地址(摘自discuz)
function getIp(){
    $ip='未知IP';
    if(!empty($_SERVER['HTTP_CLIENT_IP'])){
        return is_ip($_SERVER['HTTP_CLIENT_IP'])?$_SERVER['HTTP_CLIENT_IP']:$ip;
    }elseif(!empty($_SERVER['HTTP_X_FORWARDED_FOR'])){
        return is_ip($_SERVER['HTTP_X_FORWARDED_FOR'])?$_SERVER['HTTP_X_FORWARDED_FOR']:$ip;
    }else{
        return is_ip($_SERVER['REMOTE_ADDR'])?$_SERVER['REMOTE_ADDR']:$ip;
    }
}
function is_ip($str){
    $ip=explode('.',$str);
    for($i=0;$i<count($ip);$i++){  
        if($ip[$i]>255){  
            return false;  
        }  
    }  
    return preg_match('/^[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}$/',$str);  
}