I have three relatively similar knockout models in my application and I would like to extend a base model to combine common properties rather than repeat myself three times.
example
var ItemModel = function (item) {
var self = this;
self.order = ko.observable(item.order);
self.title = ko.observable(item.title);
self.price = ko.observable(item.price);
self.type = ko.observable(item.type);
};
var StandardItemModel = function (item, cartItemTypes) {
var self = this;
self.order = ko.observable(item.order);
self.title = ko.observable(item.title);
self.price = ko.observable(item.price);
self.type = ko.observable(item.type);
self.isInCart = ko.computed(function () {
return cartItemTypes().indexOf(item.type) > -1;
}, self);
self.itemClass = ko.computed(function () {
return self.isInCart() ? "icon-check" : "icon-check-empty";
}, self);
};
var CustomItemModel = function (item) {
var self = this;
self.order = ko.observable(item.order);
self.title = ko.observable(item.title);
self.price = ko.observable(item.price);
self.type = ko.observable(item.type);
self.icon = item.icon;
};
I would like to use ItemModel as a base class and just add the extra properties as necessary.