public function postXml($url, array $data)    {        // pack xml        $xml = $this->arrayToXml($data);        // curl post        $ch = curl_init();        curl_setopt($ch, CURLOPT_TIMEOUT, 30);        curl_setopt($ch, CURLOPT_URL, $url);        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE);        curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, FALSE);        curl_setopt($ch, CURLOPT_HEADER, FALSE);        curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);        curl_setopt($ch, CURLOPT_POST, TRUE);        curl_setopt($ch, CURLOPT_POSTFIELDS, $xml);        $response = curl_exec($ch);        if (!$response) {            throw new Exception('CURL Error: ' . curl_errno($ch));        }        curl_close($ch);        // unpack xml        return $this->xmlToArray($response);    }    public function arrayToXml(array $data)    {        $xml = "
     
      ";        foreach ($data as $k => $v) {            if (is_numeric($v)) {                $xml .= "<{$k}>{$v}
      ";            } else {                $xml .= "<{$k}>
      ";            }        }        $xml .= "
     ";        return $xml;    }    public function xmlToArray($xml)    {        return json_decode(json_encode(simplexml_load_string($xml, 'SimpleXMLElement', LIBXML_NOCDATA)), true);    }