Ember.js ArrayProxy includes() 方法

Ember.js ArrayProxy includes() 方法

Ember.js 是一个基于模型-视图-控制器(MVC)架构用于开发大型客户端Web应用程序的开源JavaScript框架。Ember.js是最广泛使用的前端应用程序框架之一,旨在加快开发速度和提高生产力。目前,许多网站都在使用Ember.js,包括Square、Discourse、Groupon、LinkedIn、Live Nation、Twitch和Chipotle。

includes() 方法用于确定数组是否包含传递的对象。

语法:

includes( object, startAt );

参数:

  • object: 在数组中我们要检查的对象。
  • startAt: 我们从中搜索对象的位置。

返回值: 如果数组中找到对象,则返回true。

安装和运行Ember.js的步骤:

要运行下面的示例,您需要有一个Ember项目。要创建一个项目,您需要先安装ember-cli。在终端中编写以下代码:

npm install ember-cli

现在你可以通过输入以下代码来创建该项目:

ember new <project-name> --lang en

启动服务器,请输入:

ember serve

示例1

输入以下代码以生成此示例的路线:

ember generate route include1

app/routes/include1.js

import Route from '@ember/routing/route'; 
  
export default class ListRoute extends Route { 
    list = [1, 2, 3, 5, 6, 7, 8, 9]; 
    item; 
    idx; 
    model() { 
        return this.list; 
    } 
    setupController(controller, model) { 
        super.setupController(controller, model); 
        controller.set('list', this.list); 
        controller.set('item', this.item); 
        controller.set('idx', this.idx); 
    } 
}

app/controllers/include1.js

import Ember from 'ember'; 
import { clear, insertAt, indexOf, lastIndexOf, includes } 
    from '@ember/array'; 
  
export default Ember.Controller.extend({ 
    actions: { 
        insertItem(item) { 
            this.list.addObject(item); 
        }, 
        clearList() { 
            this.list.clear(); 
        }, 
        contains(item) { 
            let res = this.list.includes(item); 
            alert(`The list {res ? '' : 'does not'} 
            contains{item}`); 
        }, 
    }, 
});

app/templates/include1.hbs

{{page-title "include"}} 
<h3>Here is a list of Items: </h3> 
<ul> 
    {{#each @model as |i|}} 
        <li>{{i}}</li> 
    {{/each}} 
</ul> 
<br/> 
<div> 
    <label>Enter Item: </label> 
    {{input value=this.item2}} 
</div> 
<div> 
    <input 
        type="button"
        id="contains-item"
        value="Contains?"
        {{action "contains" this.item}} 
    /> 
</div> 
<br /> 
<div> 
    <label>Enter Item: </label> 
    {{input value=this.item}} 
</div> 
<div> 
    <input 
        type="button"
        id="insert-item"
        value="Insert Item"
        {{action "insertItem" this.item }} 
    /> 
</div> 
<br /> 
<input type="button" id="clear-items" value="Clear"
    {{action "clearList"}} /> 
{{outlet}}

输出: 访问 localhost:4200/include1 查看输出

Ember.js ArrayProxy includes() 方法

示例2

输入以下代码生成此示例的路由:

ember generate route include2

app/routes/include.js

import Route from '@ember/routing/route'; 
  
export default class PartyRoute extends Route { 
    partyItems = [ 
        'Oxygen', 
        'Source Code', 
        'Infine', 
        'Tenet', 
        'SpiderHead', 
        'The Thing', 
        'A Quiet Place', 
        'The Invisible Man', 
        'Looper', 
        'Ad Astra'
    ]; 
  temp = [ 
        'Shutter Island', 
        'Matrix', 
        'Avatar', 
        'Fantastic Beast', 
        'Avengers', 
        'Fantastic four', 
        'Hult', 
        'Superman', 
        'Spiderman', 
        'The Batman'
    ]; 
    item; 
    idx; 
    model() { 
        return this.partyItems; 
    } 
    setupController(controller, model) { 
        super.setupController(controller, model); 
        controller.set('partyItems', this.partyItems); 
        controller.set('item', this.item); 
        controller.set('idx', this.idx); 
    controller.set('temp', this.temp); 
    } 
}

app/controllers/include2.js

import Ember from 'ember'; 
import { insertAt, indexOf, lastIndexOf, includes } 
    from '@ember/array'; 
  
export default Ember.Controller.extend({ 
    actions: { 
        insertItem(item) { 
            this.partyItems.pushObject( item); 
        }, 
        push_item(data) { 
            this.partyItems.pushObjects(data); 
        }, 
        contains(item) { 
            let res = this.partyItems.includes(item); 
            alert(`The partyItems {res ? '' : 'does not'} 
            contains{item}`); 
        }, 
    }, 
});

app/templates/include2.hbs

{{page-title "Party"}} 
<h3>Here is a list of items: </h3> 
<ul> 
    {{#each @model as |party|}} 
        <li>{{party}}</li> 
    {{/each}} 
</ul> 
<br /><br /> 
<div> 
    <label>Enter Item: </label> 
    {{input value=this.item}} 
</div> 
<div> 
    <input 
        type="button"
        id="insert-item"
        value="Insert Item"
        {{action "insertItem" this.item}} 
    /> 
</div> 
<br /> 
<div> 
    <label>Enter Item: </label> 
    {{input value=this.item2}} 
</div> 
<div> 
    <input 
        type="button"
        id="contains-item"
        value="Contains?"
        {{action "contains" this.item2}} 
    /> 
</div> 
<br /> 
<input 
        type="button"
        id="contains-item"
        value="Add Movies"
        {{action "push_item" this.temp}} 
    /> 
{{outlet}}

输出: 访问 localhost:4200 / include2 来查看输出

Ember.js ArrayProxy includes() 方法

参考: https://api.emberjs.com/ember/2.14/classes/Ember.Array/methods/include?anchor=include

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