php获取用户（客户端）真实IP地址的三种方法

[peng]

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(!preg_match ('/^(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);
}

[peng]

<?
/**
* 获得用户的真实IP地址
*
* @access public
* @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);
$realip = !empty($onlineip[0]) ? $onlineip[0] : '0.0.0.0';

echo "Hello, $realip \n";

return $realip;
}

real_ip();
?>