javascript - Knockout Js - 将单个项目从 json 数组绑定(bind)到元素

Question

我有以下包含元素数组的 View 模型

   function ReservationsViewModel() {
        var self = this;


        self.availableMeals = [
            { mealName: "Standard (sandwich)", price: 0, id = 1 },
            { mealName: "Premium (lobster)", price: 34.95, id = 2 },
            { mealName: "Ultimate (whole zebra)", price: 290, id = 3 }
        ];  
  }

我想将此 View 模型绑定(bind)到输入，但我只想绑定(bind)具有 id 值作为输入的 data-id 属性的单个数组元素膳食名称。

<input type="text" id="firstElementMealName" data-id="1" data-bind="value: ??"></input>

在这个例子中，我将绑定(bind) id = 1 的数组元素，文本将显示为“Standard (Sandwich)”，但我仍然需要完整的绑定(bind)和更改跟踪(observables)以及所有其他好东西 knockout 。

如何获取数据 ID 并在绑定(bind)代码中使用它来将适当的膳食绑定(bind)到输入？

提前致谢

Answer 1

建议的解决方案:

   function ReservationsViewModel() {
        var self = this;


        self.availableMeals = ko.observableArray([
            { mealName: "Standard (sandwich)", price: 0, id = 1 },
            { mealName: "Premium (lobster)", price: 34.95, id = 2 },
            { mealName: "Ultimate (whole zebra)", price: 290, id = 3 }
        ]);

        self.getMealById = function(id) {
            ko.utils.filterArray(self.availableMeals(), function(item) {
                return item.id == id;
            });
        };
  }

在 View 中:

<input type="text" id="firstElementMealName" data-bind="value: getMealById(1)"></input>

---

编辑:这是一个双向解决方案:

function ReservationsViewModel() {
        var self = this;


    self.availableMeals = ko.observable({            
        id_1: { mealName: "Standard (sandwich)", price: ko.observable(0) },
        id_2: { mealName: "Premium (lobster)", price: ko.observable(34.95) },
        id_3: { mealName: "Ultimate (whole zebra)", price: ko.observable(290) }
        });
  }

ko.applyBindings(new ReservationsViewModel());

在 View 中:

<input type="text" id="firstElementMealName" data-bind="value: availableMeals().id_2.price()"></input>