Salesforce Salesforce Certifications JAVASCRIPT-DEVELOPER-I Questions & Answers

• Question 101:

  Developer removes the HTML class attribute from the checkout button, so now it is simply:

  Checkout.

  There is a test to verify the existence of the checkout button, however it looks for a button with class= "blue". The test fails because no such button is found.

  Which type of test category describes this test?

  A. True positive

  B. True negative

  C. False positive

  D. False negative

  Correct Answer: D

• Question 102:

  Refer to the code below:

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

  Which two statements result in the array [1, 2, 3, 4, 5] ?

  Choose 2 answers

  A. [ ]. Concat.apply ([ ], inArray);

  B. []. Concat (... inArray);

  C. [ ]. concat.apply(inArray, [ ]);

  D. [ ]. concat ( [ ....inArray ] );

  Correct Answer: AB

• Question 103:

  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. Sum () (20)

  B. Sum (5, 5) ()

  C. sum() (5, 5)

  D. sum(5)(5)

  E. sum(10) ()

  Correct Answer: CD

• Question 104:

  A developer creates a class that represents a blog post based on the requirement that a Post should have a body author and view count.

  The Code shown Below:

  ClassPost {

  // Insert code here

  This.body =body

  This.author = author;

  this.viewCount = viewCount;

  }

  }

  Which statement should be inserted in the placeholder on line 02 to allow for a variable to be set to a new instanceof a Post with the three attributes correctly populated?

  A. super (body, author, viewCount) {

  B. Function Post (body, author, viewCount) {

  C. constructor (body, author, viewCount) {

  D. constructor() {

  Correct Answer: C

• Question 105:

  is below:

  

  The JavaScript portion is:

  01 function previewFile(){

  02const preview = document.querySelector(`img');

  03 const file = document.querySelector(`input[type=file]').files[0];

  04 //line 4 code

  05 reader.addEventListener("load", () => {

  06 preview.src = reader.result;

  07 },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?

  A. 04 const reader = new File(); 08 if (file) URL.createObjectURL(file);

  B. 04 const reader = new FileReader(); 08 if (file) URL.createObjectURL(file);

  C. 04 const reader = new File(); 08 if (file) reader.readAsDataURL(file);

  D. 04 const reader = new FileReader(); 08 if (file) reader.readAsDataURL(file);

  Correct Answer: D

• Question 106:

  Considering type coercion, what does the following expression evaluate to? True + `13' + NaN

  A. ` 113Nan '

  B. 14

  C. ` true13 '

  D. ` true13NaN '

  Correct Answer: D

• Question 107:

  Given the JavaScript below:

  01 function filterDOM (searchString) {

  02 const parsedSearchString = searchString andand searchString.toLowerCase() ;

  03 document.quesrySelectorAll(` .account' ) . forEach(account => (

  04 const accountName = account.innerHTML.toLOwerCase(); 05 account. Style.display = accountName.includes(parsedSearchString) ? /*Insert code*/;

  06 )};

  07 }

  Which code should replace the placeholder comment on line 05 to hide accounts that do not match thesearch string?

  A. ` name ' : ` block '

  B. ` Block ' : ` none '

  C. ` visible ' : ` hidden '

  D. ` hidden ' : ` visible '

  Correct Answer: B

• Question 108:

  Given the code below:

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

  What is the value of copy?

  A. -- [ \"false\" , { } ]-

  B. -- [ false, { } ]-

  C. -- [ \"false\" , false, undefined ]-

  D. -- [ \"false\" ,false, null ]-

  Correct Answer: D

• Question 109:

  Refer to the code below:

  let o = {

  get js() {

  let city1 = String("st. Louis");

  let city2 = String(" New York");

  return {

  firstCity: city1.toLowerCase(),

  secondCity: city2.toLowerCase(),

  }

  }

  }

  What value can a developer expect when referencing o.js.secondCity?

  A. Undefined

  B. ` new york '

  C. ` New York '

  D. An error

  Correct Answer: B

• Question 110:

  Refer to the code below:

  Let textValue = '1984';

  Which code assignment shows a correct way to convert this string to an integer?

  A. let numberValue = Number(textValue);

  B. Let numberValue = (Number)textValue;

  C. Let numberValue = textValue.toInteger();

  D. Let numberValue = Integer(textValue);

  Correct Answer: A