签名示例（PHP）

<?php
class
{
    /**
     * 签名及请求示例
     * @param $mchId string 聚合平台商户号
     * @param $secretKey string 聚合平台密钥
     * @param $appid string 微信appid
     * @param $order array 支付订单
     * @return  array
     */
    function test_jsapi_get($mchId, $secretKey, $appid ,$order)
    {
        $notify_url="callback.php";
        $ip = $_SERVER['HTTP_X_FORWARDED_FOR'];
        $randsi = date("YmdHis") . rand(1000, 9999);

        $array=
            [
                "mch_id"=>$mchId,
                "timestamp"=>time(),
                "nonce_str"=>$randsi,
                "sign_type"=>'MD5',
                "content"=>json_encode([
                    "payment"=>'WXPAY',
                    "trade_type"=>'JSAPI',
                    "client_ip"=>$ip,
                    "out_trade_no"=>$order['orderid'],
                    "fee"=>$order['money'] * 100,
                    "body"=>$order['name'],
                    "open_id"=>,
                    "device_id"=>'',
                    "shop_id"=>'',
                    "notify_url"=>$notify_url,
                    "app_id"=>$appid
                ],JSON_UNESCAPED_UNICODE),
            ];
        foreach ($array as $k => $v)
        {
            $Parameters[$k] = $v;
        }
        //签名步骤一：按字典序排序参数
        ksort($Parameters);
        $buff = "";
        ksort($Parameters);
        foreach ($Parameters as $k => $v) {
            $buff .= $k . "=" . $v . "&";
        }
        $String = '';
        if (strlen($buff) > 0) {
            $String = substr($buff, 0, strlen($buff) - 1);
        }
        $String = $String . "&secret_key=" . $secretKey;
        //签名步骤三：MD5加密
        $String = md5($String);
        //签名步骤四：所有字符转为大写
        $strings = strtoupper($String);
        $array['sign'] = $strings;
        $res = json_decode(self::http_post('https://pay.kudianvip.com/openapi/pay/unifiedpay',json_encode($array)), true);

        if($res['code'] != 0){
            return ReturnError('错误信息为：'.$res['msg']);
        }
        //返回参数格式设计
        if (!empty($res['result']))
        {
            $res_data=json_decode($res['result'],true);
            $pay_info = $res_data['pay_info'];
            if (!empty($pay_info)){
                //$jsApiParameters=$pay_info;
                $jsApiParameters['appId'] = $pay_info['app_id'];
                $jsApiParameters['timeStamp'] = $pay_info['timestamp'];
                $jsApiParameters['nonceStr'] = $pay_info['nonce_str'];
                $jsApiParameters['package'] = $pay_info['package'];
                $jsApiParameters['signType'] = $pay_info['sign_type'];
                $jsApiParameters['paySign'] = $pay_info['pay_sign'];
                return ReturnSuccess('jsapi',$jsApiParameters);
            }else{
                $this->AddLogAlert('调起支付错误','参数：'.json_encode($array).'|结果：'.$pay_info);
                return ReturnError('错误信息为：'.$res['msg']);
            }
        }else
        {
            $this->AddLogAlert('调起支付错误','参数：'.json_encode($array).'|结果：'.json_encode($res));
            return ReturnError('错误信息为：'.$res['msg']);
        }
    }

    /**
     * 使用http_post提交
     * @param $url
     * @param $params
     * @param bool $contentType
     * @return bool|mixed|string
     */
    protected function http_post($url, $params, $contentType=true)
    {

        if (function_exists('curl_init')){
            // curl方式
            $oCurl = curl_init();
            if (stripos($url, 'https://') !== FALSE){
                curl_setopt($oCurl, CURLOPT_SSL_VERIFYPEER, FALSE);
                curl_setopt($oCurl, CURLOPT_SSL_VERIFYHOST, FALSE);
            }
            $string = $params;
            if (is_array($params)){
                $aPOST = array();
                foreach ($params as $key => $val) {
                    $aPOST[] = $key . '=' . urlencode($val);
                }
                $string = join('&', $aPOST);
            }
            curl_setopt($oCurl, CURLOPT_URL, $url);
            curl_setopt($oCurl, CURLOPT_RETURNTRANSFER, 1);
            curl_setopt($oCurl, CURLOPT_POST, TRUE);
            //$contentType json处理
            if($contentType){
                $headers = array(
                    "Content-type: application/json;charset='utf-8'",
                );

                curl_setopt($oCurl, CURLOPT_HTTPHEADER, $headers);
                curl_setopt($oCurl, CURLOPT_POSTFIELDS, $params);
            }else{
                curl_setopt($oCurl, CURLOPT_POSTFIELDS, $string);
            }
            $response = curl_exec($oCurl);
            curl_close($oCurl);
            return $response;
        } elseif (function_exists('stream_context_create')) {
            // php5.3以上
            $opts = array(
                'http' => array(
                    'method' => 'POST',
                    'header' => 'Content-type: application/x-www-form-urlencoded',
                    'content' => http_build_query($params),
                )
            );
            $_opts = stream_context_get_params(stream_context_get_default());
            $context = stream_context_create(array_merge_recursive($_opts['options'], $opts));
            return file_get_contents($url, false, $context);
        }else{
            return FALSE;
        }
    }
}
?>