Ember.js Component set()函数

Ember.js是一个开源JavaScript框架，用于开发基于模型-视图-控制器(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。它是为了加快发展和提高生产力。目前，它被大量的网站使用，包括Square, Discourse, Groupon, Linked In, Live Nation, Twitch, Chipotle。

set()方法设置属性的键为传入的值。这个方法等同于object。keyName = value。

语法:

set( keyName, value );

参数:

• keyName: 要检索的属性名。
• value: 它是要设置的值。

返回值: 返回传入值的对象。

安装和运行Ember.js的步骤:

步骤1: 下面的例子在ember项目中运行。首先需要安装ember-cli。在终端中编写以下代码:

npm install ember-cli

步骤2: 现在，你可以输入以下代码来创建项目:

ember new <project-name> --lang en

要启动服务器，输入:

ember serve

示例1: 输入以下代码来生成这个例子的路由:

ember generate route set1

app/components/arr.js

import Component from '@glimmer/component';
import Ember from 'ember';
import EmberObject from '@ember/object';
import { action, without, set, get } from '@ember/object';

const Fruit = EmberObject.extend({
    init() {
        alert(`${this.get('name')} is in list Now`);
    }
});
export default Ember.Component.extend({

    fruits: [
        {
            'name': 'Lady Finger',
            'isFruit': false,
            'color': 'green'
        },
        {
            'name': 'Brinjal',
            'isFruit': false,
            'color': 'purple'
        },
        {
            'name': 'Apple',
            'isFruit': true,
            'color': 'red'
        },
        {
            'name': 'Grapes',
            'isFruit': true,
            'color': 'green'
        },
        {
            'name': 'Mango',
            'isFruit': true,
            'color': 'yellow'
        },
        {
            'name': 'Watermelon',
            'isFruit': true,
            'color': 'red'
        },
        {
            'name': 'Orange',
            'isFruit': true,
            'color': 'orange'
        }
    ],

    @action
    insertItem(data, data1, data2) {
        let temp = Fruit.create({
            name: data,
            isFruit: data1,
            color: data2
        });
        this.fruits.addObject(temp);
    },
    @action
    removeItem(data) {
        let temp = this.fruits.find(
            (item) => item.color == data)
        this.fruits.set('[]', this.fruits.without(temp));
    },
})

app/components/arr.hbs

<h3>{{yield}}</h3>
<table>
    <tr>
        <th>Name</th>
        <th>Fruit</th>
        <th>Color</th>
    </tr>
    {{#each this.fruits as |detail|}}
        <tr>
            <td>{{detail.name}}</td>
            <td>{{detail.isFruit}}</td>
            <td>{{detail.color}}</td>
        </tr>
    {{/each}}
</table>
<br /><br />
<div>
    <label>Enter Fruit Name: </label>
    {{input value=this.item1}}
</div><br />
<div>
    <label>Item is Fruit: </label>
    {{input value=this.item2}}
</div><br />
<div>
    <label>Enter Fruit color: </label>
    {{input value=this.item3}}
</div><br />
<div>
    <input
        type="button"
        id="insert-item"
        value="Insert Fruit"
        {{action "insertItem" this.item1 this.item2 this.item3}}
    />
</div>
<br />
<div>
    <label>Enter Fruit color: </label>
    {{input value=this.item4}}
</div><br />
<div>
    <input
        type="button"
        id="remove-item"
        value="Remove Fruit"
        {{action "removeItem" this.item4}}
    />
</div>
{{outlet}}

app/templates/set1.hbs

<Arr>
    <h3>Fruit's List :</h3>
</Arr>

输出:

示例2: 输入以下代码来生成这个例子的路由:

ember generate route set2

app/components/arr2.js

import Component from '@glimmer/component';
import { tracked } from '@glimmer/tracking';
import { action } from '@ember/object';
import Ember from 'ember';

let Student = Ember.Object.extend({

    // These will be supplied by `create`
    firstName: null,
    lastName: null,

    init() {
        alert(`{this.get('Name')} is Listed`);
    },
    fullName: Ember.computed('firstName',    'lastName', function () {
        return `{this.firstName} {this.lastName}`;
    }),

    Changed: Ember.observer('fullName', function () {
        console.log(`fullName changed to:{this.fullName}`);
    }),
});

export default Ember.Component.extend({
    students: [{
        Name: 'Balit',
        skill: 'Python',
        Id: 'stu2',
    },
    {
        Name: 'Permu',
        skill: 'PHP',
        Id: 'stu0',
    },
    {
        Name: 'Sam',
        skill: 'R',
        Id: 'stu1',
    },
    {
        Name: 'Pokhu',
        skill: 'JavaScript',
        Id: 'stu3',
    },
    {
        Name: 'Tanu',
        skill: 'Java',
        Id: 'stu4',
    },
    {
        Name: 'Arabh',
        skill: 'c++',
        Id: 'stu5',
    }], 
    @tracked
    item3: 'Gulshan',
    @tracked
    item2: 'Angular',
    @tracked
    item1: 'stu6',
    @tracked
    item4: 'Sam',

    @action
    print(data1, data2, data3) {
        let temp = Student.create({
            Name: data1,
            skill: data2,
            Id: data3
        });
        this.students.addObject(temp);
    },
    @action
    remove(data1) {
        let temp = this.students.find(
        (item) => item.Name == data1)
        this.students.set('[]', 
            this.students.without(temp));
    }
})

app/components/arr2.hbs

{{yield}}
<table>
    <tr>
        <th>Name</th>
        <th>skill</th>
        <th>Id</th>
    </tr>
    {{#each this.students as |detail|}}
    <tr>
        <td>{{detail.Name}}</td>
        <td>{{detail.skill}}</td>
        <td>{{get detail "Id"}}</td>
    </tr>
    {{/each}}
</table>
<br />
<div>
    <label>Enter Student FirstName: </label>
    {{input value=this.item3}}
</div>
<br />
<div>
    <label>Enter Student LastName: </label>
    {{input value=this.item2}}
</div>
<br />
<div>
    <label>Enter Student Id: </label>
    {{input value=this.item1}}
</div>
<br />
<input
    type="button"
    id="set-code"
    value="Update Student details"
    {{action "print" this.item3 this.item2 this.item1}}
/>
<br />
<br />
<div>
    <label>Enter Student Name: </label>
    {{input value=this.item4}}
</div>
<br />
<input
    type="button"
    id="remove-student"
    value="Remove Student"
    {{action "remove" this.item4}}
/>

app/templates/set2.hbs

<Arr2>
    <h3>Student's List :</h3>
</Arr2>

输出:

参考: https://api.emberjs.com/ember/4.6/classes/Component/methods/set?anchor=set