JavaScript-Developer-I Salesforce Certified JavaScript Developer (JS-Dev-101) Free Practice Exam Questions (2025 Updated)

Universal Containers (UC) notices that its application that allows users to search for

accounts makes a network request each time a key is pressed. This results in too many

requests for the server to handle.

● Address this problem, UC decides to implement a debounce function on string change

handler.

What are three key steps to implement this debounce function?

Choose 3 answers:

Refer to the code below?

Let searchString = ‘ look for this ’;

Which two options remove the whitespace from the beginning of searchString?

Choose 2 answers

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

Choose 3 answers

Which two code snippets showworking examples of a recursive function?

Choose 2 answers

Given the code below:

01 function GameConsole (name) {

02 this.name = name;

03 }

04

05 GameConsole.prototype.load = function(gamename) {

06 console.log( ` $(this.name) is loading agame : $(gamename) …`);

07 )

08 function Console 16 Bit (name) {

09 GameConsole.call(this, name) ;

10 }

11 Console16bit.prototype = Object.create ( GameConsole.prototype) ;

12 //insert code here

13 console.log( ` $(this.name) is loading a cartridge game :$(gamename) …`);

14 }

15 const console16bit = new Console16bit(‘ SNEGeneziz ’);

16 console16bit.load(‘ Super Nonic 3x Force ’);

What should a developer insert at line 15 to output the following message using the

method ?

> SNEGeneziz is loading a cartridgegame: Super Monic 3x Force . . .

Refer to the following code:

What is the value of output on line 11?

A developer has the following array of student test grades:

Let arr = [ 7, 8, 5, 8, 9 ];

The Teacher wants to double each score and then see an array of the students

who scored more than 15 points.

How should thedeveloper implement the request?

Given the JavaScript below:

Which code should replace the placeholder comment on line 05 to highlight accounts that match the search string'

Universal Containers (UC) just launched anew landing page, but users complain that the website is slow. A developer found some functions any that might cause this problem. To verify this, the developer decides to execute everything and log the time each of these three suspicious functions consumes.

Which function can the developer use to obtain the time spent by every one of the three functions?

A developer initiates a server with the file server,js and adds dependencies in the source codes package,json that are required to run the server.

Which command should the developer run to start the server locally?

Given the requirement to refactor the code above to JavaScript class format, which class

definition is correct?

A)

B)

C)

D)

Refer to the code snippet below:

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

For (let i =0; i

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

array.splice(i, 1);

}

}

What is the value of the array after the code executes?

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?

A developer writes the code below to calculate the factorial of a given number

function sum(number){

return number * sum(number-1);

}

sum(3);

what is the result of executing the code.

developer uses the code below to format a date.

After executing, what is the value offormattedDate?

A developer wants to use a module called DataPrettyPrint. This module exports one default functioncalled printDate ().

How can a developer import and use the printDate() function?

A)

B)

C)

D)

A developer wants to create an object from a function in the browser using the code

below:

Function Monster() { this.name = ‘hello’ };

Const z = Monster();

What happens due to lackof the new keyword on line 02?

Universal Container(UC) just launched a new landing page, but users complain that the

website is slow. A developer found some functions that cause this problem.To verify this, the

developer decides to do everything and log the time each of these three suspicious functions

consumes.

console.time(‘Performance’);

maybeAHeavyFunction();

thisCouldTakeTooLong();

orMaybeThisOne();

console.endTime(‘Performance’);

Which function can the developer use to obtain the time spent by every one of the three

functions?

Which three options show valid methods for creating a fat arrow function?

Choose 3 answers