Embeer.js MutableArray clear()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。

clear()方法删除数组中的所有元素

用法:

clear()

参数：它不需要任何参数。

返回值：一个空数组。

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 details

应用程序/路线/details.js


import Route from "@ember/routing/route"; 
  
export default class DetailsRoute extends Route { 
    details = [ 
        { 
            name: "Anubhav", 
            mobile: "1298119967", 
            age: 20, 
            salary: 10000, 
            city: "Patna", 
            country: "India", 
            gender: "M", 
            zipCode: "800020", 
        }, 
        { 
            name: "Sakshi", 
            mobile: "1234567890", 
            age: 17, 
            salary: 2000, 
            city: "Mumbai", 
            country: "India", 
            gender: "F", 
            zipCode: "400001", 
        }, 
        { 
            name: "Satyam", 
            mobile: "2222222222", 
            age: 42, 
            salary: 230000, 
            city: "Delhi", 
            country: "India", 
            gender: "M", 
            zipCode: "110012", 
        }, 
        { 
            name: "Shivam", 
            mobile: "1122113322", 
            age: 33, 
            salary: 122200, 
            city: "Patna", 
            country: "India", 
            gender: "M", 
            zipCode: "530068", 
        }, 
        { 
            name: "Ayushi", 
            mobile: "2244668800", 
            age: 11, 
            salary: 100, 
            city: "Jaipur", 
            country: "India", 
            gender: "F", 
            zipCode: "302001", 
        }, 
        { 
            name: "Yeshwant", 
            mobile: "1133557799", 
            age: 19, 
            salary: 5000, 
            city: "Chennai", 
            country: "India", 
            gender: "M", 
            zipCode: "600001", 
        }, 
        { 
            name: "Siddhant", 
            mobile: "9911000000", 
            age: 65, 
            salary: 992130, 
            city: "Mangalore", 
            country: "India", 
            gender: "M", 
            zipCode: "574142", 
        }, 
        { 
            name: "Khushi", 
            mobile: "8888888888", 
            age: 10, 
            salary: 0, 
            city: "Pune", 
            country: "India", 
            gender: "F", 
            zipCode: "111045", 
        }, 
    ]; 
    model() { 
        return this.details; 
    } 
    setupController(controller, model) { 
        super.setupController(controller, model); 
        controller.set("details", this.details); 
    } 
}

应用程序/控制器/details.js


import Ember from "ember"; 
import { any, slice, reverseObjects,  
    rejectBy } from "@ember/array"; 
  
export default Ember.Controller.extend({ 
    actions: { 
        getAllNames() { 
            let tempItems = this.details.getEach("name"); 
            let str = ""; 
            for (let i = 0; i < tempItems.length; i++) 
                str += tempItems[i] + "\n"; 
            alert(str); 
        }, 
        allAdult() { 
            let res = this.details.every( 
                (person) => person.age > 18); 
            alert(`${res ? "YES" : "NO"}`); 
        }, 
        getFemale() { 
            let tempItems = this.details.filter( 
                (person) => person.gender === "F"); 
            let str = ""; 
            for (let i = 0; i < tempItems.length; i++) 
                str += tempItems[i].name + "\n"; 
            alert(str); 
        }, 
        increaseSalary() { 
            this.details.forEach( 
                (person) => Ember.set(person, "salary",  
                person.salary + 1000) 
            ); 
        }, 
        hideNumber() { 
            this.details.map((person) => 
                Ember.set(person, "mobile", "**********")); 
        }, 
        clearAll() { 
            this.details.clear(); 
        }, 
    }, 
});

应用程序/模板/details.hbs


{{page-title "Details"}} 
<h3>List of People: </h3> 
<br /><br /> 
<table> 
    <tr> 
        <th>Name</th> 
        <th>Gender</th> 
        <th>Age</th> 
        <th>Salary</th> 
        <th>Mobile</th> 
        <th>City</th> 
        <th>Country</th> 
        <th>Zip Code</th> 
    </tr> 
    {{#each @model as |detail|}} 
    <tr> 
        <td>{{detail.name}}</td> 
        <td>{{detail.gender}}</td> 
        <td>{{detail.age}}</td> 
        <td>{{detail.salary}}</td> 
        <td>{{detail.mobile}}</td> 
        <td>{{detail.city}}</td> 
        <td>{{detail.country}}</td> 
        <td>{{detail.zipCode}}</td> 
    </tr> 
    {{/each}} 
</table> 
  
<br /><br /> 
<input type="button" id="get-all" 
    value="Get All Names" 
    {{action "getAllNames" }} /> 
<br /><br /> 
  
<input type="button" id="get-all-adult" 
    value="Is there only adult?" 
    {{action "allAdult" }} /> 
<br /><br /> 
  
<input type="button" id="get-female" 
    value="Get Female" 
    {{action "getFemale" }} /> 
<br /><br /> 
  
<input type="button" id="increase-salary" 
    value="Increase Salary" 
    {{action "increaseSalary" }} /> 
<br /><br /> 
  
<input type="button" id="hide-number" 
    value="Hide Number" 
    {{action "hideNumber" }} /> 
<br /><br /> 
  
<input type="button" id="clear-all" 
    value="Clear" {{action "clearAll" }} />

输出：访问 localhost:4200/details 查看输出

示例 2：键入以下代码以生成本示例的路由：

ember generate route list

应用程序/路线/list.js


import Route from "@ember/routing/route"; 
  
export default class ListRoute extends Route { 
    list = ["a", "a", "v", "c", "c", "a", 
        "d", "q", "b", "z", "a"]; 
    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); 
    } 
}

应用程序/控制器/list.js


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

应用程序/模板/list.hbs


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

输出：访问 localhost:4200/list 查看输出

参考： https://api.emberjs.com/ember/4.4/classes/MutableArray/methods

相关用法

注：本文由纯净天空筛选整理自aayushmohansinha大神的英文原创作品 Ember.js MutableArray clear() 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。