Salesforce Salesforce Certifications JAVASCRIPT-DEVELOPER-I Questions & Answers

• Question 81:

  Refer to the following code:

  

  What isthe value of output on line 11?

  A. [1, 2]

  B. [`'foo'', `'bar'']

  C. [`'foo'':1, `'bar'':2'']

  D. An error will occur due to the incorrect usage of the for...of statement on line 07.

  Correct Answer: D

• Question 82:

  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" ?

  A. Change line 7 to ) () ;

  B. Change line 2 to console.log(`Hello' , name() );

  C. Change line 9 to sayHello(world) ();

  D. Change line 5 to function world ( ) {

  Correct Answer: B

• Question 83:

  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 functionlisten(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

  A. On line 02, use event.first to test if it is the first execution.

  B. On line 04, useevent.stopPropagation ( ),

  C. On line 04, use button.removeEventListener(` click" , listen);

  D. On line 06, add an option called once to button.addEventListener().

  Correct Answer: CD

• Question 84:

  Refer to the code below:

  

  Line 05 causes an error.

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

  A. Greeting is Hello and salutation is Hello, Hello.

  B. Greeting is Goodbye and salutation isHello, Hello.

  C. Greeting is Goodbye and salutation is I say Hello.

  D. Greeting is Hello and salutation is I say hello.

  Correct Answer: A

• Question 85:

  Which two code snippetsshow working examples of a recursive function?

  Choose 2 answers

  A. Let countingDown = function(startNumber) { If ( startNumber >0) { console.log(startNumber) ; return countingDown(startNUmber); } else { return startNumber; }};

  B. Function factorial ( numVar ) { If (numVar < 0) return; If ( numVar === 0 ) return 1; return numVar -1;

  C. Const sumToTen = numVar => { If (numVar < 0) Return; return sumToTen(numVar + 1)};

  D. Const factorial =numVar => { If (numVar < 0) return; If ( numVar === 0 ) return 1; returnnumVar * factorial ( numVar - 1 ); };

  Correct Answer: AD

• Question 86:

  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

  A. Integration

  B. Black box

  C. White box

  D. Mocking

  Correct Answer: CD

• Question 87:

  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. document.addEventListener(`'onDOMContextLoaded', personalizeWebsiteContext);

  B. window.addEventListener(`load',personalizeWebsiteContext);

  C. window.addEventListener(`onload', personalizeWebsiteContext);

  D. Document.addEventListener(``'DOMContextLoaded' , personalizeWebsiteContext);

  Correct Answer: B

• Question 88:

  Teams at Universal Containers (UC) work on multiple JavaScript projects at the same time.

  UC is thinking about reusability and how each team can benefit from the work of others.

  Going open-source or public is not an option at this time.

  Which option is available to UC with npm?

  A. Private packages can be scored, andscopes can be associated to a private registries.

  B. Private registries are not supported by npm, but packages can be installed via URL.

  C. Private packages are not supported, but they can use another package manager like yarn.

  D. Private registries are not supported by npm, but packages can be installed via git.

  Correct Answer: A

• Question 89:

  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 to schedule this function?

  A. setTimeout(formatName(), 5000, "John", "BDoe");

  B. setTimeout (formatName('John', `'Doe'), 5000);

  C. setTimout(() => { formatName("John', 'Doe') }, 5000);

  D. setTimeout ('formatName', 5000, 'John", "Doe');

  Correct Answer: D

• Question 90:

  Refer to the code below:

  console.log(`'start);

  Promise.resolve(`Success') .then(function(value){

  console.log(`Success');

  });

  console.log(`End');

  What is the output after the code executes successfully?

  A. End Start Success

  B. Start Success End

  C. Start End Success

  D. Success Start End

  Correct Answer: C