Unable to receive json data in controller with knockout

Question

I am new with knockout and mvc, so I need some help, my question is my dropdown list is populating successfully from server, and on clicking save button calls Save method in controller. But problem is that in controller I am unable to receive json data i.e it is null. here is my code in view

    var initialData = @Html.Raw( new System.Web.Script.Serialization.JavaScriptSerializer().Serialize(Model)); 


    var viewModel = function(){
        var self = this;
        self.HomeAgencies = ko.observableArray(initialData.HomeAgencies);
        self.selectedOrgUnit = ko.observable();
        self.Save = function () {
                                    $.ajax({
                                    url: "@Url.Action("Save")",
                                    type: "POST",
                                    data: ko.toJSON(this),
                                    contentType: "application/json; charset=utf-8",
                                    dataType:"json",
                                    success: function(result) {alert(result.message)}
                                    });
                                }
    }

    var vm = new viewModel();
    ko.applyBindings(vm);

Where in controller i have following code

public JsonResult Save(string someData) { var message = string.Format("Saved {0} ", "successfully"); return Json(new { message }); }

string someData is always null, where I am expecting some json data.

Sławomir Rosiek Sławomir Rosiek · Accepted Answer · 2013-02-14T19:23:05

Try to replace this to self in data and introduce field name and remove contentType.

$.ajax({
    url: '@Url.Action("Save")',
    type: 'POST',
    data: { someData: ko.toJSON(self) },
    dataType: 'json',
    success: function (result) { alert(result.message); }
});

In your case context of the method can be changed from your object to html element that invoked them method or to window.

Unable to receive json data in controller with knockout

2 Answers