Javascript Knockoutjs不更新视图

当启动Javascript（信号器）函数时，我使用knockoutjs更新我的Html视图。但是调用

producthub.client.showOnlineUser

时，视图不会更新。每次应用绑定时，表多次具有相同的内容。如何在knockoutjs中更新视图

Html:

---

userOnlineOnUrl

是一个JSON数组，它在每次函数调用时更改其数据。视图（表）未使用其数据进行更新。

尽量不要每次调用模型，只使用函数进行更新

  $(document).ready(function () {
          var applied = false;
          var model;
          function ReservationsViewModel() {
                    var self = this;
                    self.seats = ko.observableArray();
                }
          model = new ReservationsViewModel();
          ko.applyBindings(model);
          applied = true;

          producthub.client.showOnlineUser = function (userOnlineOnUrl, msg1) {                   
                model  = new ReservationsViewModel();
                //remove the previous data in array
                model.seats.removeAll();
                //Add new data to array 
                model.seats(userOnlineOnUrl);

                $('#onlineUsers').append(msg1);
            };
        });

$(document).ready(function () {
     var applied = false;
     var model;
     producthub.client.showOnlineUser = function (userOnlineOnUrl, msg1) {
        function ReservationsViewModel() {
            var self = this;
            self.seats = ko.observableArray(userOnlineOnUrl);
        }

        model  = new ReservationsViewModel();
        if (!applied) {
            ko.applyBindings(model);
            applied = true;
        }

    };
});

  $(document).ready(function () {
          var applied = false;
          var model;
          function ReservationsViewModel() {
                    var self = this;
                    self.seats = ko.observableArray();
                }
          model = new ReservationsViewModel();
          ko.applyBindings(model);
          applied = true;

          producthub.client.showOnlineUser = function (userOnlineOnUrl, msg1) {                   
                model  = new ReservationsViewModel();
                //remove the previous data in array
                model.seats.removeAll();
                //Add new data to array 
                model.seats(userOnlineOnUrl);

                $('#onlineUsers').append(msg1);
            };
        });