php ip 城市（百度地图）

注：前往百度地图api开放平台登录

　　在控制台创建一个应用

　　拿到访问应用的AK

代码：

function getClientIP()
    {
        $realip = '';
        $unknown = 'unknown';
        if (isset($_SERVER)){
        if(isset($_SERVER['HTTP_X_FORWARDED_FOR']) && !empty($_SERVER['HTTP_X_FORWARDED_FOR']) && strcasecmp($_SERVER['HTTP_X_FORWARDED_FOR'], $unknown)){
        $arr = explode(',', $_SERVER['HTTP_X_FORWARDED_FOR']);
        foreach($arr as $ip){
        $ip = trim($ip);
        if ($ip != 'unknown'){
        $realip = $ip;
        break;
        }
        }
        }else if(isset($_SERVER['HTTP_CLIENT_IP']) && !empty($_SERVER['HTTP_CLIENT_IP']) && strcasecmp($_SERVER['HTTP_CLIENT_IP'], $unknown)){
        $realip = $_SERVER['HTTP_CLIENT_IP'];
        }else if(isset($_SERVER['REMOTE_ADDR']) && !empty($_SERVER['REMOTE_ADDR']) && strcasecmp($_SERVER['REMOTE_ADDR'], $unknown)){
        $realip = $_SERVER['REMOTE_ADDR'];
        }else{
        $realip = $unknown;
        }
        }else{
        if(getenv('HTTP_X_FORWARDED_FOR') && strcasecmp(getenv('HTTP_X_FORWARDED_FOR'), $unknown)){
        $realip = getenv("HTTP_X_FORWARDED_FOR");
        }else if(getenv('HTTP_CLIENT_IP') && strcasecmp(getenv('HTTP_CLIENT_IP'), $unknown)){
        $realip = getenv("HTTP_CLIENT_IP");
        }else if(getenv('REMOTE_ADDR') && strcasecmp(getenv('REMOTE_ADDR'), $unknown)){
        $realip = getenv("REMOTE_ADDR");
        }else{
        $realip = $unknown;
        }
        }
        $realip = preg_match("/[d.]{7,15}/", $realip, $matches) ? $matches[0] : $unknown;
        return $realip;
    }
    //获取所在城市
    public function getCity()
    {
        // 获取当前位置所在城市
        $getIp = $this->getClientIP();
　　　　　// url中的ak参数换成 百度地图api开放平台中拿到的AK
        $content = file_get_contents("http://api.map.baidu.com/location/ip?ak={$ak}&ip={$getIp}&coor=bd09ll");
        $json = json_decode($content);
        $address = $json->{'content'}->{'address'};//按层级关系提取address数据
        $data['address'] = $address;
        $return['province'] = mb_substr($data['address'],0,3,'utf-8');
        $return['city'] = mb_substr($data['address'],3,3,'utf-8');
        return $return;
    }