PHP获取客户端IP

/**
* 获取客户端ip
*
* @link http://www.cnblogs.com/belie8/articles/2368957.html * @return string
* @author http://my.oschina.net/wuzhencan/blog */
public function getClientIp(){
$ip = '';
$xip = $_SERVER['HTTP_X_FORWARDED_FOR'];
$cip = $_SERVER['HTTP_CLIENT_IP'];
$rip = $_SERVER['REMOTE_ADDR'];

//使用代理服务器情况
if($xip && strcasecmp($xip, 'unknown')) {
if(false !== strpos($xip,',')) {
$ipArr = explode(',',$xip);
foreach($ipArr as $val) {
if(trim(strtolower($val)) != 'unknown') {
$ip = $val;
break;
}
}
} else {
$ip = $xip;
}
} elseif($cip && strcasecmp($cip, 'unknown')) {
$ip = $cip;
} elseif($rip && strcasecmp($rip, 'unknown')) {
$ip = $rip;
}

preg_match("/[\d\.]{7,15}/", $ip, $match);
return $match[0] ? $match[0] : 'unknown';
}

http://www.cnblogs.com/belie8/articles/2368957.html