微信公众号支付（MVC版本）

  /// <summary>
  /// 获取微信支付相关信息
  /// </summary>
  /// <returns></returns>
  [HttpGet]
  public virtual ActionResult Index()
  {
   JsApiPay jsApiPay = new JsApiPay();
   OStudent model = null;
   try
   {
    //调用【网页授权获取用户信息】接口获取用户的openid和access_token
    jsApiPay.GetOpenidAndAccessToken();
    //获取微信支付者公共id
    jsApiPay.openid = jsApiPay.openid;

    string ID = Request["ID"]; //如果要获取页面传递过来的值,需修改GetOpenidAndAccessToken()方法里面的代码,加上Request.Url.Query获取参数
    model = OStudentSiteService.GetByKey(id).AppendData as OStudent;
    if (model != null)
    {
     jsApiPay.total_fee = 1;//测试 订单金额(1表示分,正式金额要*100)
     jsApiPay.Order_ID = model.order_ID; //订单号(自己定义订单号)     
    }

    //JSAPI支付预处理
    //调用统一下单，获得下单结果
    WxPayData unifiedOrderResult = jsApiPay.GetUnifiedOrderResult();
    //从统一下单成功返回的数据中获取微信浏览器调起jsapi支付所需的参数
    var wxJsApiParam = jsApiPay.GetJsApiParameters(); //获取到的是json格式字符串
    ViewBag.wxJsApiParam = wxJsApiParam; //前台页面js调用
    Log.Debug(this.GetType().ToString(), "wxJsApiParam : " + wxJsApiParam);
   }
   catch (Exception ex)
   {
    Response.Write(ex.Message + "," + ex.Source);
    Response.End();
   }
   return View(model);
  }
  
  //修改支付方式
  [HttpPost]
  public virtual JsonResult PayMethod()
  {
   AjaxJsonResult ajax = new AjaxJsonResult() { err = true, msg = string.Empty, timeout = 3 };
   string id = Request.Form["id"];
   string payMethod = Request.Form["payMethod"];
   var model = (Project.Core.Models.Model.OStudent)OStudentSiteService.GetByKey(id).AppendData;
   model.payMethod = payMethod; //支付方式
   OperationResult result = OStudentSiteService.Modify(model);
   if (result.ResultType == OperationResultType.Success)
   {
    ajax.err = false;
    ajax.msg = "操作成功";
   }
   return Json(ajax);
  }


  /// <summary>
  /// 修改支付状态
  /// </summary>
  /// <param name="userID"></param>
  /// <returns></returns>
  [HttpPost]
  public virtual string EditPayStatus(Guid userID)
  {
   string msg = "error";
   var model = OStudentSiteService.GetByKey(userID).AppendData as OStudent;
   model.Status = (int)X.Project.Site.Models.Enum.PayStatus.Success; //付款成功
   OperationResult result = OStudentSiteService.Modify(model);
   if (result.ResultType == OperationResultType.Success)
   {
    msg = "ok";    
   }
   return msg;
  }
  
  前台Index.chtml视图页面JS代码
 
  <script type="text/javascript">
  var _wxJsApiParam = eval('(@Html.Raw(ViewBag.wxJsApiParam))');

  function callpay() {
   //选择支付方式
   var payMethod = $("input[name='PayMethod']:checked").val();
   if (payMethod == "" || payMethod == null) {
    layer.msg("请选择支付方式", function () { })
    return false;
   }

   $.ajax({
    type: "POST",
    dataType: "JSON",
    url: '@Url.Action("PayMethod", "WeChatWeb")',
    data: {
     payMethod: payMethod,
     id: '@Model.ID'
    },
    success: function (data) {
     //表示修改支付方式成功
     if (!data.err) {

      //1表示微信支付,则调用微信支付
      if (payMethod == "1") {
       if (typeof WeixinJSBridge == "undefined") {
        if (document.addEventListener) {
         document.addEventListener('WeixinJSBridgeReady', jsApiCall, false);
        }
        else if (document.attachEvent) {
         document.attachEvent('WeixinJSBridgeReady', jsApiCall);
         document.attachEvent('onWeixinJSBridgeReady', jsApiCall);
        }
       }
       else {
        jsApiCall();
       }
      } else if (payMethod == "2") {
       layer.alert('恭喜您,操作成功!', function () {
         window.location.href = "@Url.Action(MVC.Default.Index())" ; //操作成功后的跳转页面
       });
      }

    } else {
     layer.msg("操作失败", function () { })
     return false;
    }
    }
   });
 }

 //调用微信JS api 支付
 function jsApiCall() {
  WeixinJSBridge.invoke('getBrandWCPayRequest', _wxJsApiParam,
    function (res) {
     if (res.err_msg == "get_brand_wcpay_request:cancel") {
 
      layer.msg("已取消支付", function () { });
      return false;
     } else if (res.err_msg == "get_brand_wcpay_request:ok") {
      //支付成功
      //ajax
      $.ajax({
       type: "POST",
       dataType: "text",
       url: '@Url.Action("EditPayStatus", "WeChatWeb")',
       data: {
        userID: '@Model.ID'
       },
       error: function (request) {
 
        layer.msg("服务器错误！", function () { });
        return false;
       },
       success: function (data) {
        window.location.href = "@Url.Action(MVC.Default.Index())"; //支付成功后跳转的页面
       }
      }); //ajax end
      }
    });
   }  
</script>