Ember.js ArrayProxy reduce() 方法

Ember.js 是一个用于开发基于模型-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。它旨在加快开发速度和提高生产效率。目前，许多网站都在使用Ember.js，包括Square、Discourse、Groupon、LinkedIn、Live Nation、Twitch和Chipotle。

reduce() 方法用于将数组的值合并为一个单一值。

语法：

reduce( callback, initialValue );

参数：

callback： 它是在数组的每个元素上执行的回调函数。
initialValue： 它是回调函数的初始值。

返回值： 一个被减少的值。

安装和运行Ember.js的步骤：

要运行以下示例，您需要一个Ember项目。要创建一个项目，您需要首先安装ember-cli。在终端中写入以下代码：

npm install ember-cli

现在你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

输入以下代码以生成此示例的路由：

ember generate route reduce1

app/routes/reduce1.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/reduce1.js

import Ember from 'ember'; 
import { pushObject, reduce, reject, removeAt, removeObject, pushObjects }  
from '@ember/array'; 
  
export default Ember.Controller.extend({ 
    actions: { 
        insertItem(item) { 
            this.partyItems.pushObject(item); 
        }, 
        push_item(data) { 
            this.partyItems.pushObjects(data); 
        }, 
        print_item() { 
            let ans = this.partyItems.reduce((acc, curr) =>  
            acc += '\n' + curr); 
            alert(ans) 
        }, 
        searchItem(data) { 
            let ans = this.partyItems.reject((movie) => 
            movie.slice(0, 1) != data); 
            alert(ans.join('\n')) 
        }, 
        removeItem(data) { 
            this.partyItems.removeObject(data); 
  
        }, 
        removeItemAt(data) { 
            this.partyItems.removeAt(JSON.parse(data)); 
        }, 
    }, 
});

app/templates/reduce1.hbs

{{page-title "reduce"}} 
<h3>Here is a list of items: </h3> 
<ul> 
    {{#each @model as |party|}} 
        <li>{{party}}</li> 
    {{/each}} 
</ul> 
<br /> 
<div> 
    <label>Enter character: </label> 
    {{input value=this.item}} 
</div> 
<div> 
    <input 
        type="button"
        id="search-item"
        value="Seach Movie Name Start with latter"
        {{action "searchItem" this.item}} 
    /> 
</div> 
<br /> 
<div> 
    <label>Enter Index: </label> 
    {{input value=this.item4}} 
</div> 
<div> 
    <input 
        type="button"
        id="remove-item-At"
        value="Remove Movie At index"
        {{action "removeItemAt" this.item4}} 
    /> 
</div> 
<br /> 
<div> 
    <label>Enter Item: </label> 
    {{input value=this.item3}} 
</div> 
<div> 
    <input 
        type="button"
        id="remove-item"
        value="Remove Movie"
        {{action "removeItem" this.item3}} 
    /> 
</div> 
<br /> 
<div> 
    <label>Enter Item: </label> 
    {{input value=this.item2}} 
</div> 
<div> 
    <input 
        type="button"
        id="insert-item"
        value="Insert Item"
        {{action "insertItem" this.item2}} 
    /> 
</div> 
<br /> 
<input 
    type="button"
    id="contains-item"
    value="Add Movies"
    {{action "push_item" this.temp}} 
/> 
<br /><br /> 
<input 
    type="button"
    id="show-item"
    value="List All Movies"
    {{action "print_item"}} 
/> 
{{outlet}}

输出: 访问localhost:4200/reduce1 查看输出

Ember.js ArrayProxy reduce() 方法

示例2

输入以下代码以生成该示例的路线：

ember generate route reduce2

app/routes/reduce2.js

import Route from '@ember/routing/route'; 
  
export default class ListRoute extends Route { 
    list = [1, 2, 3, 5, 6, 7, 8, 9]; 
    list1 = [21, 24, 12, 22, 26, 12]; 
    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); 
        controller.set('list1', this.list1); 
    } 
}

app/controllers/reduce2.js

import Ember from 'ember'; 
import { pushObject, pushObjects , reduce, reject,  
removeAt, removeObject } 
    from '@ember/array'; 
  
export default Ember.Controller.extend({ 
    actions: { 
        insertItem(item) { 
            this.list.pushObject( JSON.parse(item)); 
        }, 
        insertItems() { 
            this.list.pushObjects( this.list1); 
        }, 
        sumItems() { 
            let ans = this.list.reduce((acc, curr)=> 
            acc+=curr); 
            alert(ans) 
        }, 
        printItems() { 
            let ans = this.list.reject((numb)=>  
            numb%2!=1); 
            alert(ans.join('\n')) 
        }, 
        removeItem(data) { 
            this.list.removeAt(JSON.parse(data)); 
              
        }, 
        removeObject(data) { 
            this.list.removeObject(JSON.parse(data)); 
              
        }, 
    }, 
});

app/templates/reduce2.hbs

{{page-title "reduce"}} 
<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.item3}} 
</div> 
<div> 
    <input 
        type="button"
        id="insert-item"
        value="Insert Item"
        {{action "insertItem" this.item3}} 
    /> 
</div> 
<br /> 
<div> 
    <label>Enter Item: </label> 
    {{input value=this.item2}} 
</div> 
<div> 
    <input 
        type="button"
        id="remove-Object"
        value="Remove Item"
        {{action "removeObject" this.item2}} 
    /> 
</div> 
<br /> 
<div> 
    <label>Enter Index: </label> 
    {{input value=this.item}} 
</div> 
<div> 
    <input 
        type="button"
        id="remove-item"
        value="Remove Item at Index"
        {{action "removeItem" this.item}} 
    /> 
</div> 
<br /> 
<div> 
    <input 
        type="button"
        id="print-item"
        value="Print Event Numbers"
        {{action "printItems"}} 
    /> 
</div><br /> 
<div> 
    <input 
        type="button"
        id="push-items"
        value="Insert more items"
        {{action "insertItems"}} 
    /> 
</div> 
<br /> 
<div> 
    <input 
        type="button"
        id="sum-item"
        value="Total sum"
        {{action "sumItems"}} 
    /> 
</div> 
{{outlet}}

输出： 访问 localhost:4200/reduce2 查看输出

Ember.js ArrayProxy reduce() 方法