Ember.js NoneLocation init()方法

Ember.js 是一个开源的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并提高生产力。目前，许多网站都在使用它，包括 Square、Discourse、Groupon、LinkedIn、Live Nation、Twitch 和 Chipotle。

init() 是一个在实例化对象时调用的方法。默认情况下，该方法什么也不做，我们需要根据我们的需求来覆盖此方法。

语法：

init(){
    // Method algorithm 
};

安装和运行Ember.js的步骤：

步骤1： 要运行以下示例，您需要拥有一个Ember项目。要创建一个项目，您首先需要安装ember-cli。在终端中输入以下代码：

npm install ember-cli

步骤2： 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，请输入：

ember serve

示例1： 输入以下代码生成此示例的路由：

ember generate route init1

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('firstName')} 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: [ 
        Student.create({ 
            firstName: 'Balit', 
            lastName: 'stark', 
            Id: 'stu2', 
        }), 
        Student.create({ 
            firstName: 'Permu', 
            lastName: 'scott', 
            Id: 'stu0', 
        }), 
        Student.create({ 
            firstName: 'Sam', 
            lastName: 'melo', 
            Id: 'stu1', 
        }), 
        Student.create({ 
            firstName: 'Pokhu', 
            lastName: 'Verma', 
            Id: 'stu3', 
        }), 
        Student.create({ 
            firstName: 'Tanu', 
            lastName: 'Agrawal', 
            Id: 'stu4', 
        }), 
        Student.create({ 
            firstName: 'Arabh', 
            lastName: 'Singh', 
            Id: 'stu5', 
        })],  
 @tracked 
item3: 'Gulshan', 
 @tracked 
item2: 'Verma', 
 @tracked 
item1: 'stu6', 
  
 @action 
print(data1, data2, data3) { 
    let temp = Student.create({ 
        firstName: data1, 
        lastName: data2, 
        Id: data3 
    }); 
    this.students.addObject(temp); 
} 
})

app/components/arr2.hbs

{{yield}} 
<table> 
    <tr> 
        <th>Name</th> 
        <th>Id</th> 
      </tr> 
      {{#each this.students as |detail|}} 
    <tr> 
        <td>{{detail.fullName}}</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}} 
/>

app/templates/init1.hbs

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

输出：

Ember.js NoneLocation init()方法

示例2： 输入以下代码以生成此示例的路由：

ember generate route init2

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); 
} 
  
})

app/components/arr.hbs

{{page-title "Init"}} 
<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 Furit"
        {{action "insertItem" this.item1 this.item2 this.item3}} 
  /> 
</div> 
{{outlet}}