Continue to Read the Salesforce Certified JavaScript Developer Free Dumps (Part 2, Q39-Q80): Start Your Salesforce Certified JavaScript Developer Exam Preparation

1. Given the code below:

const delay = sync delay => {

Return new Promise ((resolve, reject) => {

setTimeout (resolve,delay);});};

const callDelay =async () => {

const yup =await delay (1000);

console.log (1);

What is logged to the console?

2. 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

3. Given two expressions var1 and var2.

What are two valid ways to return the logical AND of the two expressions and ensure it is data type Boolean? Choose 2 answers:

4. Which code statement below correctly persists an objects in local Storage?

5. Given the following code:

Let x =null;

console.log(typeof x);

What is the output of the line 02?

6. A developer needs to test this function:

01const sum3 = (arr) => (

02if (!arr.length) return 0,

03if (arr.length === 1) return arr[0],

04if (arr.length === 2) return arr[0]+ arr[1],

05 return arr[0] + arr[1] + arr[2],

06 );

Which two assert statements are valid tests for the function?

Choose 2 answers

7. Universal Containers recently launched its new landing page to host a crowd-funding campaign. The page uses an external library to display some third-party ads.

Once the page is fully loaded, it creates more than 50 new HTML items placed randomly inside the DOM, like the one in the code below:

All the elements includes the same ad-library-item class, They are hidden by default, and they are randomly displayed while the user navigates through the page.

8. Refer to the following code:

function test (val) {

If (val === undefined) {

return ‘Undefined values!’ ;

}

if (val === null) {

return ‘Null value! ’;

}

return val;

}

Let x;

test(x);

What is returned by the function call on line 13?

9. Refer to the code below?

Let searchString = ‘look for this’;

Which two options remove the whitespace from the beginning of searchString? Choose 2 answers

10. In which situation should a developer include a try .. catch block around their function call?

11. A developer has the function, shown below, that is called when a page loads.

function onload() {

console.log(“Page has loaded!”);

}

Where can the developer see the log statement after loading the page in the browser?

12. Which function should a developer use to repeatedly execute code at a fixed interval?

13. Refer to the following code:

Let obj ={

Foo: 1,

Bar: 2

}

Let output =[],

for(let something in obj{

output.push(something);

}

console.log(output);

What is the output line 11?

14. A team that works on a big project uses npm to deal with projects dependencies.

A developer added a dependency does not get downloaded when they execute npm install.

Which two reasons could be possible explanations for this? Choose 2 answers

15. Refer to the code below:

Function changeValue(obj) {

Obj.value = obj.value/2;

}

Const objA = (value: 10);

Const objB = objA;

changeValue(objB);

Const result = objA.value;

What is the value of result after the code executes?

16. A developer is required to write a function that calculates the sum of elements in an array but is getting undefined every time the code is executed.

The developer needs to find what is missing in the code below.

Const sumFunction = arr => {

Return arr.reduce((result, current) => {

//

Result += current;

//

), 10);

);

Which option makes the code work as expected?

17. Given the code below:

FunctionmyFunction(){

A =5; Var b =1;

}

myFunction();

console.log(a);

console.log(b);

What is the expected output?

18. developer publishes a new version of a package with new features that do not break backward compatibility. The previous version number was 1.1.3.

Following semantic versioning format, what should the new package version number be?

19. Given the code below:

01 function GameConsole (name) {

02 this.name = name;

3 }

4

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

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

7 )

8 function Console 16 Bit (name) {

9 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 . . .

20. Given the code below:

const copy = JSON.stringify([ newString(‘ false ’), new Bollean( false ), undefined ]);

What is the value of copy?

21. Whichthree actions can be using the JavaScript browser console? Choose 3 answers:

22. Refer to the code below:

for (let number =2; number <= 5; number += 1) {

// insert code statement here

}

The developer needs to insert a code statement in the location shown.

The code statement has these requirements:

1. Does require an import

2. Logs an error when the boolean statement evaluates to false

3. Works in both the browser and Node.js.

Which meet the requirements?

23. Given the requirement to refactor the code above to JavaScript class format, which class definition is correct?

A)

B)

C)

D)

24. A developer at Universal Containers creates a new landing page based on HTML, CSS, and JavaScript TO ensure that visitors have a good experience, 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 on the above business requirement?

25. Refer to the code:

Given the code above, which three properties are set pet1? Choose 3 answers:

26. Considering type coercion, what does the following expression evaluate to?

True + ‘13’ + NaN

27. Which statement phrases successfully?

28. Consider type coercion, what does the following expression evaluate to?

True + 3 + ‘100’ + null

29. 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 displayed in the console.

Here is the HTML file content:

<input type =” text” value=” Hello” name =” input”>

<button type =” button” >Display </button>

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?

30. Cloud Kicks has a class to represent items for sale in an online store, as shown below:

Class Item{

constructor (name, price){

this.name = name;

this.price = price;

}

formattedPrice(){

return ‘s’ + String(this.price);}}

A new business requirement comes in that requests a ClothingItem class that should have all of the properties and methods of the Item class but will also have properties that are specific to clothes.

Which line of code properly declares the clothingItem class such that it inherits from Item?

31. 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 this new requirement?

32. 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 the developer has, which code logs an error at boost with an event?

33. Refer to the following array:

Let arr1 = [ 1,2, 3, 4, 5 ];

Which two lines of code result in a second array, arr2 being created such that arr2 is not a reference to arr1?

34. A developer is creating a simple webpage with a button. When a userclicks this button for the first time, a message is displayed.

The developer wrote the JavaScript code below, but something is missing. The message gets displayed every time a user clicks the button, instead of just the first time.

01 function listen(event) {

02 alert (‘Hey! I am John Doe’);

03 button.addEventListener (‘click’, listen);

Which two code lines make this code work as required? Choose 2 answers

35. A developer wrote a fizzbuzz function that when passed in a number, returns the following:

● ‘Fizz’ if the number is divisible by 3.

● ‘Buzz’ if the number is divisible by 5.

● ‘Fizzbuzz’ if the number is divisible by both 3 and 5.

● Empty string if the number is divisible by neither 3 or 5.

Which two test cases will properly test scenarios for the fizzbuzz function? Choose 2 answers

36. Refer to the code below:

Line 05 causes an error.

What are the values of greeting and salutation once code completes?

37. is below:

<input type=”file” onchange=”previewFile()”>

<img src=”” height=”200” alt=”Image Preview…”/>

The JavaScript portion is:

01 functionpreviewFile(){

02 const preview = document.querySelector(‘img’);

3 const file = document.querySelector(‘input[type=file]’).files[0];

4 //line 4 code

5 reader.addEventListener(“load”, () => {

6 preview.src = reader.result;

7 },false);

08 //line 8 code

09 }

In lines 04 and 08, which code allows the user to select an image from their local computer, and to display the image in the browser?

38. Which two code snippets show working examples of a recursive function? Choose 2 answers

39. The developer has a function that prints “Hello” to an input name.

To test this,thedeveloper created a function that returns “World”. However the following snippet does not print “Hello World”.

What can the developer do to change the code to print “Hello World”?

40. A developer has code that calculates a restaurant bill, but generates incorrect answers while testing the code:

function calculateBill (items) {

let total = 0;

total += findSubTotal(items);

total += addTax(total);

total += addTip(total);

return total;

}

Which option allows the developer to step into each function execution within calculateBill?

41. Refer to the code below:

Let str = ‘javascript’;

Str[0] = ‘J’;

Str[4] = ’S’;

After changing the string indexvalues, the value of str is ‘javascript’.

What is the reason for this value:

42. A developer creates an object where its properties should be immutable and prevent properties from being added or modified.

Which method should be used to execute this business requirement?

43. A developer creates a genericfunction to log custom messages in the console. To do this, the function below is implemented.

01 function logStatus(status){

02 console./*Answer goes here*/{‘Item status is: %s’, status};

03 }

Which three console logging methods allow the use of string substitution in line 02?

44. Which statement accurately describes the behaviour of the async/ await keyworks?

45. A test has a dependency on database.query. During the test the dependency is replaced with an object called database with the method, query, that returns an array. The developer needs to verify how many times the method was called and the arguments used each time.

Which two test approaches describe the requirement? Choose 2 answers

46. Which three statements are true about promises? Choose 3 answers

47. developer wants to use a module named universalContainersLib and them callfunctions

from it.

How should a developer import every function from the module and then call the functions foo and bar?

48. Refer to the code below:

01 const server = require(‘server’);

02 /* Insert code here */

A developer imports a library that creates a web server. The imported library uses events and callbacks to start the servers

Which code should be inserted at the line 03 to set up an event and start the web server?

49. catch( arr => (

10 console.log(“Race is cancelled.”, err);

11 ));

What is the value of result when Promise.race executes?

50. A developer wrote the following code:

01 let X = object.value;

02

03 try {

4 handleObjectValue(X);

5 } catch (error) {

6 handleError(error);

7 }

The developer has a getNextValue function to execute after handleObjectValue(), but does not want to execute getNextValue() if an error occurs.

How can the developer change the code to ensure this behavior?

51. Refer to code below:

Function muFunction(reassign){

Let x = 1;

var y = 1;

if (reassign) {

Let x= 2;

Var y = 2;

console.log(x);

console.log(y);}

console.log(x);

console.log(y);}

What is displayed when myFunction(true) is called?

52. A developer is leading the creation of a new browser application that will serve a single page application. The team wants to use a new web framework Minimalsit.js. The Lead developer wants to advocate for a more seasoned web framework that already has a community around it.

Which two frameworks should the lead developer advocate for? Choose 2 answers