JavaScript-Developer-I Sample Questions Answers

At Universal Containers, every team has its own way of copyingJavaScript objects. The code snippet shows an Implementation from one team:

What is the output of the code execution?

developer is trying to convince management that their team will benefit from using

Node.js for a backend server that they are going to create. The server will be a web server that

handles API requests from a website that the teamhas already built using HTML, CSS, and

JavaScript.

Which three benefits of Node.js can the developer use to persuade their manager?

Choose 3 answers:

Given code below:

setTimeout (()=> (

console.log(1);

). 0);

console.log(2);

New Promise ((resolve, reject )) = > (

setTimeout(() => (

reject(console.log(3));

). 1000);

)).catch(() => (

console.log(4);

));

console.log(5);

What is logged to the console?

A developer is trying to handle an error within a function.

Which code segment shows the correct approach to handle an error without propagating it elsewhere?

A)

B)

C)

D)

A developer is setting up a new Node.js server with a client library that is built using events and callbacks.

The library:

● Will establish a web socket connection and handle receipt of messages to theserver

● Will be imported with require, and made available with a variable called we.

The developer also wants to add error logging if a connection fails.

Given this info, which code segment shows the correct way to set up a client with two events that listen at execution time?

A developer at Universal Containers creates a new landing page based on HTML, CSS, and

JavaScript TO ensure that visitors have a goodexperience, a script named personaliseContext

needs to be executed when the webpage is fully loaded (HTML content and all related files ), in

order to do some custom initialization.

Which statement should be used to call personalizeWebsiteContent based onthe above

business requirement?

Given the following code:

What will be the first four numbers logged?

Refer to the code below:

Let foodMenu1 = [‘pizza’, ‘burger’, ‘French fries’];

Let finalMenu = foodMenu1;

finalMenu.push(‘Garlic bread’);

What is the value of foodMenu1 after the code executes?

Considering the implications of 'use strict' on line 04, which three statements describe the execution of the code?

Choose 3 answers

developer creates a new web server that uses Node.js. It imports a server library that

uses events and callbacks for handling server functionality.

The server library is imported with require and is made available to the code by a

variable named server. The developer wants to log any issues that the server has while booting

up.

Given the code and the information thedeveloper has, which code logs an error at boost

with an event?

A developer has two ways to write a function:

Option A:

function Monster() {

This.growl = () => {

Console.log (“Grr!”);

}

}

Option B:

function Monster() {};

Monster.prototype.growl =() => {

console.log(“Grr!”);

}

After deciding on an option, the developer creates 1000 monster objects.

How many growl methods are created with Option A Option B?

Refer the following code

what is the value of array after code executes?

A developer wrote the following code to test a sum3 function that takes in an array of numbers and returns the sum of the first three numbers in the array, and the test passes.

A different developer made changes to the behavior of sum3 to instead sum only the first two numbers present in the array.

Which two results occur when running this test on the updated sum3 function?

Choose 2 answers

A developer creates a simple webpage with an input field. When a user enters text in the input field and clicks the button, the actual value of the field must be displayedin the console.

Here is the HTML file content:

Display The developer wrote the javascript code below:

Const button = document.querySelector(‘button’);

button.addEvenListener(‘click’, () => (

Const input = document.querySelector(‘input’);

console.log(input.getAttribute(‘value’));

When the user clicks the button, the output is always “Hello”.

What needs to be done to make this code work as expected?

A developer creates a simple webpage with an input field. When a user enters text in

the inputfield and clicks the button, the actual value of the field must be displayed in the

console.

Here is the HTML file content:

Display

The developer wrote the javascript codebelow:

Const button = document.querySelector(‘button’);

button.addEvenListener(‘click’, () => (

Const input = document.querySelector(‘input’);

console.log(input.getAttribute(‘value’));

When the user clicks the button, the output is always “Hello”.

What needs to be done make this code work as expected?

Refer to the following array:

Let arr = [1, 2, 3, 4, 5];

Which three options result in x evaluating as [1,2]?

Choose 3 answer

Refer to the code below:

What is the value of result when the code executes?

Refer to the code below:

function changeValue(param) {

Param =5;

}

Let a =10;

Let b =5;

changeValue(b);

Const result = a+ “ - ”+ b;

What is the value of result when code executes?

A developer is working on an ecommerce website where the delivery date is dynamically

calculated based on the current day. The code line below is responsible for this calculation.

Const deliveryDate = new Date ();

Due to changes in the business requirements, the delivery date must now be today’s

date + 9 days.

Which code meets thisnew requirement?

Given the code below:

Which three code segments result in a correct conversion from number to string? Choose 3 answers

A developer has a web server running with Node.js. The command to start the web server is node server.js. The web server started having

latency issues. Instead of a one second turnaround for web requests, the developer now sees a five second turnaround.

Which command can the web developer run to see what the module is doing during the latency period?

A developer is debugging a web server that uses Node.js The server hits a runtimeerror

every third request to an important endpoint on the web server.

The developer added a break point to the start script, that is at index.js at he root of the

server’s source code. The developer wants to make use of chrome DevTools to debug.

Which command can be run to access DevTools and make sure the breakdown is hit ?

Refer to the code snippet below:

Let array = [1, 2, 3, 4, 4, 5, 4, 4];

For (let i =0; i < array.length; i++)

if (array[i] === 4) {

array.splice(i, 1);

}

}

What is the value of array after the code executes?

Refer to the following code:

Let sampleText = ‘The quick brown fox jumps’;

A developer needs to determine if a certainsubstring is part of a string.

Which three expressions return true for the given substring ?

Choose 3 answers

Refer to HTML below:

Which expression outputs the screen width of the element with the ID card-01?

Given the code below:

Setcurrent URL ();

console.log(‘The current URL is: ‘ +url );

functionsetCurrentUrl() {

Url = window.location.href:

What happens when the code executes?

A developer at Universal Containers is creating their new landing pagebased on HTML, CSS, and JavaScript. The website includes multiple external resources that are loaded when the page is opened.

To ensure that visitors have a good experience, a script named personalizeWebsiteContent needs to be executed when the webpage isloaded and there is no need to wait for the resources to be available.

Which statement should be used to call personalizeWebsiteContent based on the above business requirement?

Given the following code:

is the output of line 02?

A developer writes the code below to return a message to a user attempting to register a new username. If the username is available, a variable named nag is declared and assigned a value on line 03.

What is the value of msg when getAvailableabilityMessage (“newUserName”) is executed and get Availability (“newUserName”) returns true?

Referto the code below:

new Promise((resolve, reject) => {

const fraction = Math.random();

if( fraction >0.5) reject("fraction > 0.5, " + fraction);

resolve(fraction);

})

.then(() =>console.log("resolved"))

.catch((error) => console.error(error))

.finally(() =>console.log(" when am I called?"));

When does Promise.finally on line 08 get called?

A developer implements a function that adds a few values.

Function sum(num) {

If (num == undefined) {

Num =0;

}

Return function( num2, num3){

If (num3 ===undefined) {

Num3 =0 ;

}

Return num + num2 + num3;

}

}

Which three options can the developer invoke for this function to get a return value of 10 ?

Choose 3 answers

A developer has two ways to write a function:

Option A:

function Monster(){

this.growl = ()=>{

console.log('Grr!');

}

}

Option B:

function Monster(){};

Monster.prototype.growl = ()=>{

console.log('Grr!');

}

After deciding on an option, the developercreates 1000 monster objects.

How many growl methods are created with Option A and Option B?

A developer has a formatName function that takes two arguments, firstName and lastName and returns a string. They want to schedule the

function to run once after five seconds.

What is the correct syntax toschedule this function?