Event Handling and DOM Manipulation: Interactive Web Development

Question 1

In JavaScript, which event listener method is used to attach an event listener to an element?

Accepted Answer

addEventListener

Answer

registerEventListener

Answer

attachEvent

Answer

handleEvent

Question 2

How do you correctly add an event listener using the `addEventListener` method?

Accepted Answer

element.addEventListener(event, listener, useCapture);

Answer

element.addEventListener(listener, event, useCapture);

Answer

element.addListener(event, listener);

Answer

element.attachEvent(event, listener);

Question 3

Which of the following best practices can help optimize DOM manipulation performance?

Accepted Answer

Avoid using innerHTML

Accepted Answer

Cache DOM elements

Answer

Always use event delegation

Answer

Never remove event listeners

Question 4

In JavaScript, which method allows you to select an HTML element using its unique identifier?

Accepted Answer

getElementById()

Answer

querySelector()

Answer

getElementsByClassName()

Answer

getElementsByTagName()

Question 5

When a user interacts with an element on a web page, what is the trigger called?

Accepted Answer

Event

Answer

Listener

Answer

Handler

Answer

Function

Question 6

Which JavaScript method is used to add an event listener to an element?

Accepted Answer

addEventListener()

Answer

addEvent()

Answer

listen()

Answer

attachEvent()

Question 7

What is the purpose of the 'target' property in an event object?

Accepted Answer

To identify the element that triggered the event

Answer

To store the coordinates of the mouse cursor

Answer

To specify the type of event that occurred

Answer

To prevent the default action of the event

Question 8

Which JavaScript method is used to dynamically create an HTML element?

Accepted Answer

createElement()

Answer

createNode()

Answer

makeElement()

Answer

newElement()

Question 9

What is the purpose of the 'preventDefault()' method in JavaScript event handling?

Accepted Answer

To prevent the default action of the event from occurring

Answer

To cancel the event entirely

Answer

To stop the event from propagating to parent elements

Answer

To modify the event target

Question 10

Which JavaScript method is used to select a single element based on its ID?

Accepted Answer

getElementById()

Answer

querySelector()

Answer

getElementByClass()

Answer

selectElement()

Question 11

What is the role of the Document Object Model (DOM) in web development?

Accepted Answer

To represent the structure and content of a web page

Answer

To handle user input and interactions

Answer

To render web pages on a browser

Answer

To store data from web forms

Question 12

Which of these is NOT a standard JavaScript event type?

Accepted Answer

onhover

Answer

click

Answer

onchange

Answer

onload

Question 13

Which event occurs when the mouse cursor hovers over a specified element?

Accepted Answer

onmouseover

Answer

onfocus

Answer

onenter

Answer

onhovering

Question 14

What is the primary function of the event.preventDefault() method?

Accepted Answer

To prevent the default action associated with an event from occurring

Answer

To cancel the event entirely, stopping its propagation and execution

Answer

To prevent the event from bubbling up the DOM tree to parent elements

Question 15

Which DOM property can be used to access the element that initiated an event?

Accepted Answer

target

Answer

origin

Answer

initiator

Answer

source

Question 16

What is the result of using the document.getElementById() method?

Accepted Answer

A reference to the element with the specified ID

Answer

The innerHTML content of the element with the specified ID

Answer

A list of all elements with the specified ID

Question 17

What is the intended purpose of the Element.appendChild() method?

Accepted Answer

To insert a node as a child of another node in the DOM tree

Answer

To remove a node from its parent in the DOM tree

Answer

To replace a node with another node in the DOM tree

Question 18

Which JavaScript method can be utilized to create a new element in the DOM?

Accepted Answer

document.createElement()

Answer

Node.create()

Answer

document.getElement()

Answer

Element.create()

Question 19

What is the primary advantage of utilizing the event delegation pattern?

Accepted Answer

Enhances performance by attaching event listeners to a single parent element rather than multiple child elements

Answer

Prevents potential memory leaks by removing event listeners when they are no longer required

Question 20

Describe the key difference between the innerHTML and innerText properties.

Accepted Answer

innerHTML reflects the HTML content of an element, including tags, while innerText only contains the text content

Answer

innerHTML is a read-only property, while innerText can be modified

Answer

innerText reflects the HTML content of an element, including tags, while innerHTML only contains the text content

Question 21

In the context of JavaScript event handling, what property of the Event object specifies the element that initiated an event?

Accepted Answer

target

Answer

origin

Answer

sender

Answer

source

Question 22

Which DOM method do you use to create a new HTML element?

Accepted Answer

document.createElement('')

Answer

element.newElement('')

Answer

generateElement('')

Answer

createNode('')

Question 23

How do you append a newly created element to the end of the document's body?

Accepted Answer

document.body.appendChild(element)

Answer

element.appendToBody()

Answer

body.add(element)

Answer

document.insertAfter(element)

Question 24

Which property of the Element object represents the element's HTML content?

Accepted Answer

innerHTML

Answer

innerText

Answer

text

Answer

content

Question 25

To remove an element from the DOM, which method should you use?

Accepted Answer

element.parentNode.removeChild(element)

Answer

remove(element)

Answer

element.dispose()

Question 26

Which event is triggered when the user's mouse hovers over an element?

Accepted Answer

mouseover

Answer

hover

Answer

enter

Answer

mousemove

Question 27

How do you prevent the default action of an event from occurring?

Accepted Answer

event.preventDefault()

Answer

event.stop()

Answer

event.disable()

Answer

event.cancel()

Question 28

Which method is used to access or modify the computed style of an element?

Accepted Answer

element.style

Answer

element.css

Answer

element.computedStyle

Answer

getStyle(element)

Question 29

How do you add a CSS class to an element using JavaScript?

Accepted Answer

element.classList.add('className')

Answer

className.add(element)

Answer

element.style.className = 'className'

Answer

element.addClass('className')