You can do the same in more observable style
Html
<select data-bind="options: vehicleTypes, optionsText: 'Name', value: selectedVehicle">
</select>
<pre data-bind="text: ko.toJSON($root, null, 2)"></pre>
JavaScript
var ViewModel = function() {
var Vehicle = function(name, type) {
this.Name = name;
this.Type = type;
};
this.vehicleTypes = ko.observableArray([
new Vehicle("Aluth", "New"),
new Vehicle("parana", "Used")
]);
this.selectedVehicle = ko.observable();
this.selectedVehicle.subscribe(function(newValue) {
alert(newValue.Name);
alert(newValue.Type);
}, this);
};
ko.applyBindings(new ViewModel());
Here is full version: jsfiddle