更新可观察到的淘汰赛和下拉菜单

Question

I have an ASPX page with a dropdown select bound with Knockout.JS. On the page load I check the url for a parameter and update the view if their is a parameter which you can see in my API. I've changed the API to leave out unnecessary code because it returns the value needed. My problem is that I cannot get my observable SelectedView to update to "Notes". Any advice?

ASPX:

       <asp:DropDownList runat="server" data-bind="value: SelectedView" id="viewselect">
           <asp:ListItem>Select A View</asp:ListItem>
           <asp:ListItem>Notes</asp:ListItem>
           <asp:ListItem>Credit Manager</asp:ListItem>
       </asp:DropDownList>

View Model:

function CustomerViewModel() {

    this.self = this;
    self.SelectedCustomer = ko.observable();
    self.SelectedView = ko.observable();
}

API:

$(document).ready(function () {

 var custnmbr = "123456";

 if (custnmbr != "") {
     var notes = "Notes";
     self.SelectedView(notes);
 }

});

Answer 1

I guess if you look in console you 'll get error:

Uncaught TypeError: Object [object global] has no method 'SelectedView' 

Because in your $(document).ready you are using the object self which is only defined inside CustomerViewModel() .

To solve this, you need to call .SelectedView(notes); on the object instance you are passing to ko.applyBindings ,

UPDATE

for example:

function CustomerViewModel() {
    this.self = this;
    self.SelectedCustomer = ko.observable();
    self.SelectedView = ko.observable();
}
var customerObj=new CustomerViewModel();
ko.applyBindings(customerObj);

// later in your code.
customerObj.SelectedView(notes);