curl发送xml , xml和数组互转

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)
    {
        $xml = "<xml>";
        foreach ($data as $k => $v) {
            if (is_numeric($v)) {
                $xml .= "<{$k}>{$v}</{$k}>";
            } else {
                $xml .= "<{$k}><![CDATA[{$v}]]></{$k}>";
            }
        }
        $xml .= "</xml>";
        return $xml;
    }

    public function xmlToArray($xml)
    {
        return json_decode(json_encode(simplexml_load_string($xml, 'SimpleXMLElement', LIBXML_NOCDATA)), true);
    }