function onBridgeReady() {
            WeixinJSBridge.invoke(
                'getBrandWCPayRequest', {
                    "appId": $('#APPID').val(),     //公众号名称，由商户传入     
                    "timeStamp": $('#Timestamp').val(),         //时间戳，自1970年以来的秒数     
                    "nonceStr": $('#Noncestr').val(), //随机串     
                    "package": $('#package').val(),
                    "signType": "MD5",         //微信签名方式：     
                    "paySign": $('#paySign').val() //微信签名 
                },
                function (res) {
                    if (res.err_msg == "get_brand_wcpay_request:ok") {
                        //支付成功，后续自行处理
                        
                    }
                    else
                    {
                        //支付取消，或者其他错误，自行处理
                    }
                }
            );
        }        　

//这里通过官方的一个实体，用户自行使用，我这里是直接读取的CONFIG文件
private static Senparc.Weixin.MP.TenPayLibV3.TenPayV3Info tenPayV3Info = new Senparc.Weixin.MP.TenPayLibV3.TenPayV3Info(ConfigurationManager.AppSettings["corpId"], ConfigurationManager.AppSettings["corpSecret"], ConfigurationManager.AppSettings["mch_id"]
                    , ConfigurationManager.AppSettings["key"], ConfigurationManager.AppSettings["v3url"]);

        /// <summary>
        /// 微信预支付
        /// </summary>
        /// <param name="attach"></param>
        /// <param name="body"></param>
        /// <param name="openid"></param>
        /// <param name="price"></param>
        /// <param name="orderNum"></param>
        /// <returns></returns>
        public static string PayInfo(string attach, string body, string openid, string price, string orderNum = "1833431773763549")
        {
            RequestHandler requestHandler = new RequestHandler(HttpContext.Current);
            //微信分配的公众账号ID（企业号corpid即为此appId）
            requestHandler.SetParameter("appid", tenPayV3Info.AppId);
            //附加数据，在查询API和支付通知中原样返回，该字段主要用于商户携带订单的自定义数据
            requestHandler.SetParameter("attach", attach);
            //商品或支付单简要描述
            requestHandler.SetParameter("body", body);
            //微信支付分配的商户号
            requestHandler.SetParameter("mch_id", tenPayV3Info.MchId);
            //随机字符串，不长于32位。
            requestHandler.SetParameter("nonce_str", TenPayUtil.GetNoncestr());
            //接收微信支付异步通知回调地址，通知url必须为直接可访问的url，不能携带参数。
            requestHandler.SetParameter("notify_url", tenPayV3Info.TenPayV3Notify);
            //trade_type=JSAPI，此参数必传，用户在商户公众号appid下的唯一标识。
            requestHandler.SetParameter("openid", openid);
            //商户系统内部的订单号,32个字符内、可包含字母，自己生成
            requestHandler.SetParameter("out_trade_no", orderNum);
            //APP和网页支付提交用户端ip，Native支付填调用微信支付API的机器IP。
            requestHandler.SetParameter("spbill_create_ip", "127.0.0.1");
            //订单总金额，单位为分，做过银联支付的朋友应该知道，代表金额为12位，末位分分
            requestHandler.SetParameter("total_fee", price);
            //取值如下：JSAPI，NATIVE，APP，我们这里使用JSAPI
            requestHandler.SetParameter("trade_type", "JSAPI");
            //设置KEY
            requestHandler.SetKey(tenPayV3Info.Key);

            requestHandler.CreateMd5Sign();
            requestHandler.GetRequestURL();
            requestHandler.CreateSHA1Sign();
            string data = requestHandler.ParseXML();
            requestHandler.GetDebugInfo();

            //获取并返回预支付XML信息
            return TenPayV3.Unifiedorder(data);
        }
    }

public class ShareInfo
    {
        string corpId = string.Empty;
        public string CorpId
        {
            get { return corpId; }
            set { corpId = value; }
        }
        string ticket = string.Empty;

        public string Ticket
        {
            get { return ticket; }
            set { ticket = value; }
        }
        string noncestr = string.Empty;

        public string Noncestr
        {
            get { return noncestr; }
            set { noncestr = value; }
        }
        string timestamp = string.Empty;

        public string Timestamp
        {
            get { return timestamp; }
            set { timestamp = value; }
        }

        private string paySign = string.Empty;
        public string PaySign
        {
            get { return paySign; }
            set { paySign = value; }
        }

        private string package = string.Empty;

        public string Package
        {
            get { return package; }
            set { package = value; }
        }
    }

public static ShareInfo GetPayInfo(string prepayid)
        {
            shareInfo = new ShareInfo();
            //检查是否已经注册jssdk
            if (!JsApiTicketContainer.CheckRegistered(corpId))
            {
                JsApiTicketContainer.Register(corpId, corpSecret);
            }
            JsApiTicketResult jsApiTicket = JsApiTicketContainer.GetTicketResult(corpId);
            JSSDKHelper jssdkHelper = new JSSDKHelper();
            shareInfo.Ticket = jsApiTicket.ticket;
            shareInfo.CorpId = corpId.ToLower();
            shareInfo.Noncestr = JSSDKHelper.GetNoncestr().ToLower();
            shareInfo.Timestamp = JSSDKHelper.GetTimestamp().ToLower();
            shareInfo.Package="prepay_id=" + prepayid.ToLower();

            RequestHandler requestHandler = new RequestHandler(HttpContext.Current);

            requestHandler.SetParameter("appId", shareInfo.CorpId);
            requestHandler.SetParameter("timeStamp", shareInfo.Timestamp);
            requestHandler.SetParameter("nonceStr", shareInfo.Noncestr);
            requestHandler.SetParameter("package", shareInfo.Package);
            requestHandler.SetParameter("signType", "MD5");

            requestHandler.SetKey(tenPayV3Info.Key);
            requestHandler.CreateMd5Sign();
            requestHandler.GetRequestURL();
            requestHandler.CreateSHA1Sign();
            shareInfo.PaySign = (requestHandler.GetAllParameters()["sign"]).ToString();
            return shareInfo;
        }