javascript - 无法到达由 ko.mapping 在 javascript 中实例化的 observablesArray

Question

这是一个例子: http://jsfiddle.net/valin/W4ubQ/

如您所见，由函数 (this.features) 实例化的数组正在工作。但是由 ko.mapping (this.featuresFromJS) 实例化的数组仅适用于 View ，而不适用于 javascript 函数。我应该如何实例化 featuresFromJS 或其他内容来计算 lowTotal？

感谢任何帮助。

Answer 1

希望这会有所帮助:

function objFeatures(name, price) {
    return {
        name: ko.observable(name),
        price: ko.observable(price)
    }
}

var AppViewModel = function () {
    var self = this;
    self.featuresFromJS = ko.observableArray();

    self.features = ko.observableArray([
    new objFeatures("Feature1", 20),
    new objFeatures("Feature2", 50)]);

    var data = '[{"name":"Feature3","price":20},{"name":"Feature4","price":50}]';

    ko.mapping.fromJSON(data, {}, self.featuresFromJS);

    self.lowTotal = ko.computed(function () {
        var total = 0;
        ko.utils.arrayForEach(this.featuresFromJS(), function (item) {                
            alert("hooray!");
            total += item.price();
        });
        return total;
    }, self);

    self.grandTotal = ko.computed(function () {
        var total = 0;
        ko.utils.arrayForEach(this.features(), function (item) {
            total += item.price();
        });
        return total;
    }, self);
};

ko.applyBindings(new AppViewModel());