极客教程Ember.js MutableArray shiftObject() 方法
Ember.js 是一个基于模型-视图-控制器（MVC）架构的开源JavaScript框架，用于开发大型客户端Web应用程序。Ember.js是最广泛使用的前端应用程序框架之一。它旨在加速开发并提高生产力。目前，它被许多网站使用，包括Square、Discourse、Groupon、Linked In、Live Nation、Twitch和Chipotle。
shiftObject() 方法从数组的开头移除并返回nil（如果没有更多对象）或一个对象。
语法:
shiftObject()
参数： 不需要任何参数。
返回值： 移动后的对象。
要运行以下示例，您需要先准备一个ember项目。要创建一个项目，您需要先安装ember-cli。在终端中写入下面的代码：
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 fruits
app/routes/fruits.js
import Route from "@ember/routing/route";
import { } from "@ember/array";
export default class FruitsRoute extends Route {
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",
},
];
model() {
return this.fruits;
}
setupController(controller, model) {
super.setupController(controller, model);
controller.set("fruits", this.fruits);
}
}
app/controllers/fruits.js
import Ember from "ember";
import { shiftObject, isAny, isEvery } from "@ember/array";
export default Ember.Controller.extend({
actions: {
removeFruit() {
this.fruits.shiftObject();
},
anyFruit() {
alert(`{this.fruits.isAny("isFruit") ? "Yes" : "No"}`);
},
allFruit() {
alert(`{this.fruits.isEvery("isFruit") ? "Yes" : "No"}`);
},
},
});
app/template/fruits.js
{{page-title "Fruits"}}
<h3>Here is a list of eatables: </h3>
<ul>
{{#each @model as |eatable|}}
<li style="color: {{eatable.color}}">{{eatable.name}}</li>
{{/each}}
</ul>
<br /><br />
<input type="button"
id="remove-eatable"
value="Remove Eatable" {{action 'removeFruit' }} />
<br /><br />
<input type="button"
id="fruit-any"
value="List Contains Any Fruit?" {{action 'anyFruit' }} />
<br /><br />
<input type="button"
id="fruit-all"
value="List Contains Only Fruit?" {{action 'allFruit' }} />
{{outlet}}
输出： 访问 localhost:4200/fruits 查看输出
示例2
输入以下代码以生成此示例的路线：
ember generate route details
app/routes/details.js
import Route from '@ember/routing/route';
export default class DetailsRoute extends Route {
details = [
{
'name': 'Anubhav',
'mobile': '1298119967',
'city': 'Patna',
'country': 'India',
'gender': 'M',
'zipCode': '800020'
},
{
'name': 'Sakshi',
'mobile': '1234567890',
'city': 'Mumbai',
'country': 'India',
'gender': 'F',
'zipCode': '400001'
},
{
'name': 'Satyam',
'mobile': '2222222222',
'city': 'Delhi',
'country': 'India',
'gender': 'M',
'zipCode': '110012'
},
{
'name': 'Shivam',
'mobile': '1122113322',
'city': 'Bangalore',
'country': 'India',
'gender': 'M',
'zipCode': '530068'
},
{
'name': 'Ayushi',
'mobile': '2244668800',
'city': 'Jaipur',
'country': 'India',
'gender': 'F',
'zipCode': '302001'
}
];
someMoreDetails = [
{
'name': 'Yeshwant',
'mobile': '1133557799',
'city': 'Chennai',
'country': 'India',
'gender': 'M',
'zipCode': '600001'
},
{
'name': 'Siddhant',
'mobile': '9911000000',
'city': 'Mangalore',
'country': 'India',
'gender': 'M',
'zipCode': '574142'
},
{
'name': 'Khushi',
'mobile': '8888888888',
'city': 'Pune',
'country': 'India',
'gender': 'F',
'zipCode': '111045'
}
];
city;
code;
model() {
return this.details;
}
setupController(controller, model) {
this._super(controller, model);
controller.set('details', this.details);
controller.set('someMoreDetails', this.someMoreDetails);
controller.set('city', this.city);
controller.set('code', this.code);
}
}
app/controllers/details.js
import Ember from "ember";
import { pushObjects, shiftObject, setEach } from "@ember/array";
export default Ember.Controller.extend({
actions: {
checkCity(city) {
alert(`Contains Person from {city}:
{this.details.isAny("city", city) ? "Yes" : "No"}`);
},
checkCountry() {
alert(`All are ${this.details
.isEvery("country", "India") ? "" : "not"}
Indian`);
},
remove() {
this.details.shiftObject();
},
setZipCode(code) {
this.details.setEach("zipCode", code);
},
pushMoreDetails() {
this.details.pushObjects(this.someMoreDetails);
},
},
});
app/template/details.js
{{page-title "Details"}}
<h3>List of People: </h3>
<br/><br/>
<table>
<tr>
<th>Name</th>
<th>Gender</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.mobile}}</td>
<td>{{detail.city}}</td>
<td>{{detail.country}}</td>
<td>{{detail.zipCode}}</td>
</tr>
{{/each}}
</table>
<br/><br/>
<div>
<label>Enter City: </label>
{{input value=this.city}}
</div>
<div>
<input type="button" id="check-city"
value="Check City" {{action 'checkCity' this.city}}/>
</div>
<br/><br/>
<div>
<label>Enter Code: </label>
{{input value=this.code}}
</div>
<div>
<input type="button" id="set-code"
value="Set Zip Code" {{action 'setZipCode' this.code}}/>
</div>
<br/><br/>
<input type="button" id="remove-detail"
value="Remove" {{action 'remove'}}/>
<br/><br/>
<input type="button" id="push-details" value="Add More Details"
{{action 'pushMoreDetails'}}/>
<br/><br/>
<input type="button" id="check-country" value="All Indian?"
{{action 'checkCountry'}}/>
{{outlet}}
输出： 访问 localhost：4200/details 查看输出结果
参考资料: https://api.emberjs.com/ember/4.4/classes/MutableArray/methods