bootstrap级联下拉列表knockoutjs

Question

我有2个下拉列表。区域和分区。当我选择一个区域时，我想填充子区域下拉列表。我没有击倒所有工作但我无法弄清楚如何使用敲除数据绑定而不是js来处理更改事件。

脚本：???

html：

<div class="col-md-10">
    @Html.LabelFor(model => model.AreaID, new { @class = "control-label col-md-2" })
    @Html.DropDownList("AreaID", AreaList, new { @class = "form-control" })
    @Html.ValidationMessageFor(model => model.AreaID)
</div>

<div class="col-md-10">
    @Html.LabelFor(model => model.AreaNodeID, new { @class = "control-label col-md-2" })
    @Html.DropDownList("AreaNodeID", new List<SelectListItem>(), new { @class = "form-control" } )
    @Html.ValidationMessageFor(model => model.AreaNodeID)
</div>

Answer 1

 @Html.DropDownList("AreaID", AreaList, new { @class = "form-control" }, 
                    new { onchange = "FetchStates();" })



function FetchStates() {    
    var countryCode = $("#AreaID").val();
    $.getJSON("/Home/GetStates/" + countryCode, null, function (data) {
        objVM.states(data);
    });