public function demo() {
        $url='http://demo.com/';
        $content = '{                // Json的格式
            "serviceName": "changebusList",
            "queryParameters": {
                "page": "1",
                "userid": "66",
                "querytype": "0"
            }
        }';

        echo $htt = $this->https_post($url,$content);
    }

    //通过CURL，发送http的post请求
    public function https_post($url,$data){
        $curl = curl_init();
        curl_setopt($curl, CURLOPT_URL, $url);
        curl_setopt($curl, CURLOPT_SSL_VERIFYHOST, false);
        curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, false);
        curl_setopt($curl, CURLOPT_POST, 1);
        curl_setopt($curl, CURLOPT_POSTFIELDS, $data);
        curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);
        $result = curl_exec($curl);
        if(curl_errno($curl)) {
            return 'Errno'.curl_errno($curl);
        }
        curl_close($curl);
        return $result;
    }