Embeer.js Observable decrementProperty()用法及代码示例

Ember.js 是一个开源 JavaScript 框架，用于开发基于 Model-View-Controller (MVC) 架构的大型客户端 Web 应用程序。 Ember.js是使用最广泛的前端应用框架之一。它的目的是加速开发并提高生产力。目前，它被大量网站使用，包括 Square、Discourse、Groupon、Linked In、Live Nation、Twitch 和 Chipotle。

decrementProperty()方法用于将属性值减少到一定数量。

用法:

decrementProperty(keyName,decrement);

参数：

keyName: 它是我们要减少其值的属性的名称。
decrement: 这是我们想要减少到的值。默认值为 1。

返回值：此方法返回一个新的属性值。

安装和运行 Ember.js 的步骤：

第 1 步：要运行以下示例，您需要有一个 ember 项目。要创建一个，您需要先安装ember-cli。在终端中写入以下代码：

npm install ember-cli

第 2 步：现在您可以通过输入以下代码来创建项目：

ember new <project-name> --lang en

要启动服务器，请键入：

ember serve

示例 1：键入以下代码以生成本示例的路由：

ember generate route decrement1

应用程序/路线/decrement1.js

Javascript


import Route from '@ember/routing/route';
import EmberObject from '@ember/object';
export default class WebsitesRoute extends Route {
    temp;
    model() {
        return "Increment Property";
    }
    setupController(controller, model) {
        super.setupController(controller, model);
        // controller.set('food', this.food);
        controller.set('temp', this.temp);
        controller.set('temp2', this.temp2);
    }
}

应用程序/控制器/decrement1.js

Javascript


import Ember from 'ember';
import EmberObject from '@ember/object';
const Student = EmberObject.extend({
    toStringExtension() {
        return this.get('food');
    }
});
export default Ember.Controller.extend({
    class: 10,
    age: 15,
    student: [
        Student.create({
            Name: 'Aarbh',
            class: 12,
            age: 18,
        }),
        Student.create({
            Name: 'viky',
            class: 9,
            age: 15,
        }),
        Student.create({
            Name: 'Chiku',
            class: 8,
            age: 11,
        }),
        Student.create({
            Name: 'Nikki',
            class: 11,
            age: 17,
        }),
        Student.create({
            Name: 'Ankit',
            class: 8,
            age: 14,
        }),
        Student.create({
            Name: 'Sonam',
            class: 11,
            age: 17,
        }),
        Student.create({
            Name: 'Ravi',
            class: 10,
            age: 16,
        }),
    ],
    actions: {
        older(data) {
            this.incrementProperty(data);
        },
        younger(data) {
            this.decrementProperty(data);
        },
        addItem(data, data1, data2) {
            let temp = Student.create({
                Name: data,
                class: data1,
                age: data2
            });
            alert(temp.toString() + ' Student Added in list');
            this.student.addObject(temp);
        }
    }
});

应用程序/模板/decrement1.hbs

HTML


{{page-title "decrementProperty"}}
<h3>List of Item in Buckets</h3>
<table>
    <tr>
        <th> Name </th>
        <th>Class </th>
        <th>Age </th>
      </tr>
      {{#each this.student as |website|}}
        <tr>
             <td>{{website.Name}}</td>
              <td>{{website.class}}</td>
              <td>{{website.age}}</td>
        </tr>
      {{/each}}
</table>
<br /><br />
<div>
    <label>Enter Student Name: </label>
      {{input value=this.temp2}}
</div>
<br />
<div>
    <label>Enter Age: </label>
      {{input value=this.age}}
</div>
<input
    type="button" id="increase"
    value="+" {{action "older" "age"}} />
<input
    type="button" id="decrease"
    value="-" {{action "younger" "age"}} />
<br />
<br />
<div>
    <label>Enter Class: </label>
      {{input value=this.class}}
</div>
<input type="button" id="increase"
    value="+" {{action "older" "class"}} />
<input type="button" id="decrease"
    value="-" {{action "younger" "class"}} />
<br />
<br />
<br /><br />
<input
    type="button"
      id="all-students"
      value="Add item"
      {{action "addItem" this.temp2 this.class this.age}}
/>
{{outlet}}

输出：

减量属性输出1

参考：https://api.emberjs.com/ember/4.4/classes/Observable/methods/decrementProperty?anchor=decrementProperty

相关用法

注：本文由纯净天空筛选整理自singhanuj78276大神的英文原创作品 Ember.js Observable decrementProperty() Method。非经特殊声明，原始代码版权归原作者所有，本译文未经允许或授权，请勿转载或复制。