用户单击链接后Knockoutjs绑定

我是javascript / jquery的新手，正在学习knockoutjs . 我坚持这个问题 . 我的页面中有两个ko绑定 . 第一个创建一个用户可以单击的链接，以便查看有关该项目的更多信息 . 该链接包含一个传递给ajax调用的ID，该调用将数据返回到第二个ko observable .

问题是第二个可观察数据总是在页面上显示为“未定义” . 但是，如果我在创建observable的代码中放入console.log（数据），那么数据就在那里 . 同样，在Fiddler中，ajax调用请求的json被罚款 .

我确定这与我如何绑定observable有关，但我尝试了几种不同的方式（使用数组，没有数组等）并且无济于事 . 任何帮助或指针将不胜感激 . 看起来像一个简单的问题，但我已经尝试了一切，无法让它工作......

$(document).ready(function () {

        var da = new firstViewModel();

        ko.applyBindings(da, document.getElementById('da'));


        var eq = new secondViewModel(); 
//Binding the second observable here but not using it yet as it depends on getting data from the //first (da) in order to work.

        ko.applyBindings(eq, document.getElementById('eqdetails'));  

    });

     function da(data) {
            var self = this;
            self.eqid = ko.observable(data.eqid);
            self.modelname = ko.observable(data.modelname);

        }

    function firstViewModel() {

        // Data    
        var self = this;
    self.da = ko.observableArray([]);

    self.getdetails = function (da) {

        selectedid = da.eqid();

//Call second observable when user clicks on link. 
        var eq = new secondViewModel();
        eq.geteqdetails();

    }

    };
};


     function eqview(data) {

        console.log('in eqview ' + data); //This works, but data is still undefined in html 
        var self = this;
        self.modelname = ko.observable(data.modelname);
        self.number = ko.observable(data.number);

    };

    function secondViewModel() {

        var self = this;

        self.eqviews = ko.observableArray([]);

        self.geteqdetails = function () {

            $.ajax("../Process/GetEqDetails", {
                type: "post",
                contentType: "application/json",
                data: JSON.stringify({ EqID: selectedid }),
                success: function (result) {
                    console.log('in ajax call ' + result.data);

                    var mappedequipmentview = $.map(result, function (item) { return new eqview(item) });
                    self.eqviews(mappedequipmentview);

                }
            });

        };

这是页面的HTML：

<div id="da" class="span3">
    <table class="table table-bordered table-striped table-condensed">
        <thead>
            <tr>
                <th>Model</th>
                <th>ID</th>
            </tr>
        </thead>
        <tbody data-bind="template: { name: 'datemplate', foreach: da }">
        </tbody>
    </table>


    <script id="datemplate" type="text/html">
        <tr>
            <td><span data-bind="text: modelname"></span></td>
            <td>
                <button type="button" class="btn btn-link" data-bind="click: $root.getdetails" title="View">
                    <span data-bind="text: eqid"></span></button>
            </td>
        </tr>
    </script>
</div>


<div class="span6">

    <div class="span1">
    <table class="table table-bordered table-condensed"  id="eqdetails">
        <tbody >

            <tr>
                <td><span data-bind="text: $data.modelname "></span></td>
            </tr>
            <tr>
                <td><span data-bind="text: $data.number "></span></td>
            </tr>
        </tbody>
    </table>


    </div>



    </div>

</div>