Ember.js is an open-source JavaScript framework used for developing large client-side web applications which is based on Model-View-Controller (MVC) architecture. Ember.js is one of the most widely used front-end application frameworks. It is made to speed up development and increase productivity. Currently, it is utilized by a large number of websites, including Square, Discourse, Groupon, Linked In, Live Nation, Twitch, and Chipotle.
The objectsAt() method is used to get the objects at the given indexes.
Syntax:
objectsAt( indexes );
Parameters:
- indexes: It is the array of index items to return.
Steps to Install and Run Ember.js:
To run the following examples you will need to have an ember project with you. To create one, you will need to install ember-cli first. Write the below code in the terminal:
npm install ember-cli
Now you can create the project by typing in the following piece of code:
ember new <project-name> --lang en
To start the server, type:
ember serve
Example 1: Type the following code to generate the route for this example:
ember generate route objectsAt1
import Route from '@ember/routing/route' ;
import { classify, w } from '@ember/string' ;
import { objectsAt } from '@ember/array' ;
export default class LanguagesRoute extends Route {
name = `Hindi Korean Marathi Telugu Portuguese
Turkish Bengali Spanish`;
num = `343.9 81.7 83.1 82.0 232.4 82.3 233.7 474`;
languages = [];
initLanguages() {
this .languages = [];
this .name = w( this .name);
this .num = w( this .num);
for (let i = 0; i < this .name.length; i++) {
let obj = new Object();
obj[ 'name' ] = classify( this .name[i]);
obj[ 'num' ] = this .num[i];
this .languages.pushObject(obj);
}
}
temp1;
convert(string) {
this .item = string.split( "," ).map((item) => item.trim());
return this .item;
}
model() {
this .initLanguages();
return this .languages;
}
setupController(controller, model) {
super .setupController(controller, model);
controller.set( 'languages' , this .languages);
controller.set( 'temp1' , this .temp1);
controller.set( 'convert' , this .convert)
}
} |
import Ember from 'ember' ;
import { objectsAt } from '@ember/array' ;
export default Ember.Controller.extend({
actions: {
get_Name() {
let ans = this .languages.mapBy( 'name' );
alert(ans.join( '\n' ));
},
get_most() {
let temp = 0;
let tempItems = this .languages.map((item) =>
temp < JSON.parse(item.num) ? temp = item.name : temp);
alert(temp);
},
remove() {
this .languages.popObject();
},
check_item(idx) {
let temp = this .languages.objectAt(JSON.parse(idx));
alert(temp.name)
},
check_items(idx) {
idx = this .convert(idx);
let temp = this .languages.objectsAt(idx);
let ans = temp.mapBy( 'name' )
alert(ans.join( '\n' ))
},
},
}); |
{{page-title "objectsAt" }}
<h2>Spoken Languages in the World</h2>
<table style= "border: 2px solid black;padding: 30px;" >
<tr>
<th>Language</th>
<th>Native Speakers ( in Millions)</th>
</tr>
{{ #each @model as |language|}}
<tr>
<td>{{language.name}}</td>
<td>{{language.num}}</td>
</tr>
{{/each}}
</table> <br /><br /> <div> <label>Enter index: </label>
{{input value= this .temp}}
</div> <input type= "button"
id= "increase-pocket-money"
value= "Get Language at Index"
{{action "check_item" this .temp}}
/> <br /><br /> <div> <label>Enter indexs: </label>
{{input value= this .temp2}}
</div> <input type= "button"
id= "check-atIndex"
value= "Check at indexes"
{{action "check_items" this .temp2}}
/> <br/> <br /> <div> <input
type= "button"
id= "check-fruit"
value= "Check Most speaking Language"
{{action "get_most" }}
/>
</div> <br /> <div> <input
type= "button"
id= "remove-item"
value= "Remove Last Element"
{{action "remove" }}
/>
</div> <br /> <div> <input
type= "button"
id= "show-lang"
value= "Show Language"
{{action "get_Name" }}
/>
</div> {{outlet}} |
Output: Visit localhost:4200/objectsAt1 to view the output
Example 2: Type the following code to generate the route for this example:
ember generate route objectsAt2
import Route from "@ember/routing/route" ;
export default class StudentsRoute extends Route {
students = [
{
name: "Aaush Somankar" ,
gender: "M" ,
class: 12,
grade: "A" ,
},
{
name: "Aman Prakash" ,
gender: "M" ,
class: 10,
grade: "A" ,
},
{
name: "Siya guru" ,
gender: "F" ,
class: 11,
grade: "B" ,
},
{
name: "Ramesh verma" ,
gender: "M" ,
class: 10,
grade: "A" ,
},
{
name: "Esnoor" ,
gender: "M" ,
class: 9,
grade: "F" ,
},
{
name: "Balit" ,
gender: "M" ,
class: 10,
grade: "A" ,
},
{
name: "Dora" ,
gender: "F" ,
class: 12,
grade: "F" ,
},
{
name: "Lalu" ,
gender: "F" ,
class: 8,
grade: "A" ,
},
{
name: "Pokhraj" ,
gender: "M" ,
class: 11,
grade: "F" ,
},
{
name: "Citu" ,
gender: "M" ,
class: 8,
grade: "C" ,
},
{
name: "Rahul" ,
gender: "M" ,
class: 9,
grade: "A" ,
},
{
name: "Ram" ,
gender: "M" ,
class: 12,
grade: "A" ,
},
{
name: "Priti" ,
gender: "F" ,
class: 9,
grade: "F" ,
},
{
name: "Flip" ,
gender: "M" ,
class: 9,
grade: "B" ,
},
{
name: "Sita" ,
gender: "F" ,
class: 8,
grade: "A" ,
},
{
name: "Aashray" ,
gender: "M" ,
class: 12,
grade: "C" ,
},
{
name: "Suneel" ,
gender: "M" ,
class: 8,
grade: "C" ,
},
];
convert(string) {
this .item = string.split( "," ).map((item) => item.trim());
return this .item;
}
model() {
return this .students;
}
setupController(controller, model) {
super .setupController(controller, model);
controller.set( "students" , this .students);
controller.set( "convert" , this .convert);
controller.set( "item" , this .item);
}
} |
import Ember from "ember" ;
export default Ember.Controller.extend({
actions: {
getAllNames() {
let res = this .students.mapBy( 'name' );
alert(res.join( '\n' ));
},
allPass() {
let temp = '' ;
let tempItems = this .students.map((item) =>
item.grade == 'F' ? temp += item.name + '\n' : temp);
alert(temp);
},
remove() {
this .students.popObject();
},
check_item(idx) {
let temp = this .students.objectAt(JSON.parse(idx));
alert(temp.name)
},
check_items(idx) {
idx = this .convert(idx);
let temp = this .students.objectsAt(idx);
let ans = temp.mapBy( 'name' )
alert(ans.join( '\n' ))
},
},
}); |
{{page-title "objectsAt" }}
<h3>List of Students: </h3> <table> <tr>
<th>Name</th>
<th>Class</th>
<th>Gender</th>
<th>Grade</th>
</tr>
{{ #each @model as |student|}}
<tr>
<td>{{student.name}}</td>
<td>{{student.class}}</td>
<td>{{student.gender}}</td>
<td>{{student.grade}}</td>
</tr>
{{/each}}
</table> <br /><br /> <input type= "button"
id= "get-all"
value= "Get All Names"
{{action "getAllNames" }}
/> <br /><br /> <input type= "button"
id= "all-pass"
value= "Did Everyone Pass?"
{{action "allPass" }}
/> <br /><br /> <div> <label>Enter index: </label>
{{input value= this .temp}}
</div> <input type= "button"
id= "increase-pocket-money"
value= "Get Person at Index"
{{action "check_item" this .temp}}
/> <br /><br /> <div> <label>Enter indexs: </label>
{{input value= this .temp2}}
</div> <input type= "button"
id= "check-atIndex"
value= "Check at indexes"
{{action "check_items" this .temp2}}
/> <br /><br /> <input type= "button"
id= "remove-last"
value= "Remvoe Last Student"
{{action "remove" }}
/> {{outlet}} |
Output: Visit localhost:4200/objectsAt2 to view the output
Reference: https://api.emberjs.com/ember/4.6/classes/ArrayProxy/methods/objectsAt?anchor=objectsAt