如何将数组元素的值赋给knockout中的observable

Question

我试图从json数组中提取一个元素并将其分配给一个observable，这样当它的值在下拉列表中发生变化时，observable的值也会随着选择而改变。 observable必须取用户所做的任何选择的值，例如，如果用户选择不同的驱动程序名称，则可以更改驱动程序名称observable。这是我到目前为止所拥有的

索引页

    function PageViewModel() {
        var pvm = this;
        pvm.loginVM = new LoginViewModel();
        pvm.VehicleVM = new vehicleViewModel();
        pvm.topManagerVM = new TopManagerViewModel();
    }

   pageViewModel = new PageViewModel();
   ko.applyBindings(pageViewModel, document.getElementById("htmlTop"));

vehicle.js =＆gt;我的实际问题在哪里

function DriverViewModel() {
    var drv = this;

    drv.driverId = ko.observable(0);
    drv.driverName = ko.observable("");


}
function  vehicleViewModel{
    vvm.regNumber = ko.observable(0);
    vvm.make = ko.observable("");
    vvm.model = ko.observable("");
    vvm.model = ko.observable("");
    vvm.DriverDetail = new  DriverViewModel();
   }

function getDrivers(id) {
    if (!pageViewModel.isAuthenticated()) return;
    $.when(getSecureData("/api/vehicleDrivers/" + id))
    .done(function (driverList) {
        driverList.unshift({ "driverId": 0, "driverName": "Please select a driver..." });
        pageViewModel.DriverVM.driverList(driverList);
        var List = driverList;

        List[0] = pageViewModel.VehicleVM.driverDetail.driverId;
        List[1] = pageViewModel.vehicleVM.driverDetail.driverName;
    })
    .fail(function (message) {
        $.msgbox(message);
    });
}