Salesforce JAVASCRIPT-DEVELOPER-I Online Practice Questions and Exam Preparation

Salesforce JAVASCRIPT-DEVELOPER-I Online Questions & Answers

• Question 181:

  A class was written to represent items for purchase in an online store, and a second class Representing items that are on sale at a discounted price. THe constructor sets the name to the first value passed in. The pseudocode is below:

  Class Item {

  constructor(name, price) {

  ... // Constructor Implementation

  }

  }

  Class SaleItem extends Item {

  constructor (name, price, discount) {

  ...//Constructor Implementation

  }

  }

  There is a new requirement for a developer to implement a description method that will return a brief description for Item and SaleItem.

  Let regItem =new Item(`Scarf', 55);

  LetsaleItem = new SaleItem(`Shirt' 80, -1);

  Item.prototype.description = function () { return `This is a ' + this.name;

  console.log(regItem.description());

  console.log(saleItem.description());

  SaleItem.prototype.description = function () { return `This is adiscounted ' + this.name; }

  console.log(regItem.description());

  console.log(saleItem.description());

  What is the output when executing the code above ?

  A. This is a Scarf Uncaught TypeError: saleItem.description is not a function This is aScarf This is a discounted Shirt
  B. This is a Scarf This is a Shirt This is a Scarf This is a discounted Shirt
  C. This is a Scarf This is a Shirt This is a discounted Scarf This is a discounted Shirt
  D. This is aScarf Uncaught TypeError: saleItem.description is not afunction This is a Shirt This is a did counted Shirt
  B. This is a Scarf This is a Shirt This is a Scarf This is a discounted Shirt

• Question 182:

  Refer to the code below: Considering that JavaScript is single-threaded, what is the output of line 08 after the code executes?

  

  A. 10
  B. 11
  C. 12
  D. 13
  B. 11

• Question 183:

  A developer wants to use atry...catch statement to catch any error that countSheep () may throw and pass it to a handleError () function. What is the correct implementation of the try...catch?

  

  A. Option A
  B. Option B
  C. Option C
  D. Option D
  A. Option A

• Question 184:

  Which three statements are true about promises ? Choose 3 answers

  A. The executor of a new Promise runs automatically.
  B. A Promise has a .then() method.
  C. A fulfilled or rejected promise will not change states .
  D. A settled promise can become resolved.
  E. A pending promise can become fulfilled, settled, or rejected.
  B. A Promise has a .then() method.
  C. A fulfilled or rejected promise will not change states .
  E. A pending promise can become fulfilled, settled, or rejected.

• Question 185:

  The developer wants to test this code:

  Const toNumber =(strOrNum) => strOrNum;

  Which two tests are most accurate for this code?

  Choose 2 answers

  A. console.assert(toNumber(`2') === 2);
  B. console.assert(Number.isNaN(toNumber()));
  C. console.assert(toNumber(`-3') < 0);
  D. console.assert(toNumber () === NaN);
  A. console.assert(toNumber(`2') === 2);
  C. console.assert(toNumber(`-3') < 0);

• Question 186:

  A developer wrote the following code to test a sum3 function that takes in anarray 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. The line 05 assertion passes.
  B. The line 02 assertion passes.
  C. The line 02 assertion fails.
  D. The line 05 assertion fails.
  B. The line 02 assertion passes.
  D. The line 05 assertion fails.

• Question 187:

  Developer wants to use a module named universalContainersLiband them call functions from it.

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

  A. import * ad lib from `/path/universalContainersLib.js'; lib.foo(); lib.bar();
  B. import (foo, bar) from `/path/universalContainersLib.js'; foo(); bar();
  C. import all from `/path/universalContaineraLib.js'; universalContainersLib.foo(); universalContainersLib.bar();
  D. import * from `/path/universalContaineraLib.js'; universalContainersLib.foo(); universalContainersLib.bar();
  A. import * ad lib from `/path/universalContainersLib.js'; lib.foo(); lib.bar();

• Question 188:

  Which code change should be done for the console to log the following when 'Click me!' is clicked'

  

  > Row log > Table log

  A. Remove lines 13and 14
  B. Change line 10 to event.stopPropagation (false) ;
  C. Change line 14 to elem.addEventListener ('click', printMessage, true);
  D. Remove line 10
  B. Change line 10 to event.stopPropagation (false) ;

• Question 189:

  Refer to the code below:

  

  What is the output of this function when called with an empty array?

  A. Return 0
  B. Return 5
  C. Return NaN
  D. Return Infinity
  B. Return 5

• Question 190:

  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?

  

  A. Hello John Doe
  B. Hello Dan
  C. Hello Dan Doe
  D. SyntaxError: Unexpected token in JSON
  D. SyntaxError: Unexpected token in JSON