PHP 獲取IP所屬地區

接口文檔地址：http://ip.taobao.com/instructions.html

$ip=get_client_ip();
if(!preg_match("/^[\d]+\.[\d]+\.[\d]+\.[\d]+$/isU",$ip)){
    echo "IP地址錯誤";
}else{
    //淘寶IP接口
    $url='http://ip.taobao.com/service/getIpInfo.php?ip='.$ip;  
    $result = file_get_contents($url);  
    $result = json_decode($result,true);  
    if($result['code']!==0 || !is_array($result['data'])){
        echo "IP地址錯誤";
    }else{
        print_r($result);
    }
}

/**
 * 獲取客戶端IP地址
 * @param integer $type 返回類型 0 返回IP地址 1 返回IPV4地址數字
 * @param boolean $adv 是否進行高級模式獲取（有可能被僞裝） 
 * @return mixed
 */
function get_client_ip($type = 0,$adv=true) {
    $type       =  $type ? 1 : 0;
    static $ip  =   NULL;
    if ($ip !== NULL) return $ip[$type];
    if($adv){
        if (isset($_SERVER['HTTP_X_FORWARDED_FOR'])) {
            $arr    =   explode(',', $_SERVER['HTTP_X_FORWARDED_FOR']);
            $pos    =   array_search('unknown',$arr);
            if(false !== $pos) unset($arr[$pos]);
            $ip     =   trim($arr[0]);
        }elseif (isset($_SERVER['HTTP_CLIENT_IP'])) {
            $ip     =   $_SERVER['HTTP_CLIENT_IP'];
        }elseif (isset($_SERVER['REMOTE_ADDR'])) {
            $ip     =   $_SERVER['REMOTE_ADDR'];
        }
    }elseif (isset($_SERVER['REMOTE_ADDR'])) {
        $ip     =   $_SERVER['REMOTE_ADDR'];
    }
    // IP地址合法驗證
    $long = sprintf("%u",ip2long($ip));
    $ip   = $long ? array($ip, $long) : array('0.0.0.0', 0);
    return $ip[$type];
}