Javascript 2 Flashcards

Question 1

Q

As an HTML attribute

Answer

A

Question 2

Q

As a method

Answer

A

window.onclick = myFunction();

Question 3

Q

major drawback of using methods:

Answer

A

we can bind only one event at a time with this method.
The second binding overwrites the first, so when the
user clicks inside the browser window, only
myOtherFunction() will run.

Question 4

Q

addEventListener

Answer

A

This approach allows us to keep our logic
within our scripts and allows us to perform
multiple bindings on a single object.
We start by calling the addEventListener
method of the target object, and then
specify the event in question and the
function to be executed as two arguments.
– window.addEventListener(“click”, myFunction);

Question 5

Q

Document Object Model (DOM)

Answer

A

The DOM gives us a way to access and
manipulate the contents of a document (i.e.,
html document).
It provides a structured map of the
document, as well as a set of methods to
interface with the elements contained
therein.
– We can use it to find elements by their names or
attributes, then add, modify, or delete elements
and their content

Question 6

Q

DOM as document tree

Answer

A

Each element within the page is referred to as a node.
Each node can contain further branches.

Question 7

Q

Accessing DOM nodes

Answer

A

– The document object in the DOM identifies the
page itself.
– The document object comes with a number of
standard properties and methods for accessing
collections of elements.
– The document object comes with a number of
built-in properties containing information about
the document.

Question 8

Q

getElementById()

Answer

A

var foo = document.getElementById( “beginner” ).innerHTML;
* the statement says to look on the page (document), find the
element that has the id value “beginner”, find the HTML content
within that element (innerHTML), and save those contents to a
variable (foo).

Question 9

Q

getElementsByTagName()

Answer

A

– document.getElementsByTagName(“p”) returns every
paragraph on the page, wrapped in something called a
collection or nodeList, in the order they appear in the
document from top to bottom.
– nodeLists behave much like arrays.
- To access specific paragraphs in the nodeList, we reference
them by their index, just like an array.

var paragraphs = document.getElementsByTagName(“p”);
paragraphs[0] is a reference to the first paragraph in the document
paragraphs[1] refers to the second

Question 10

Q

getElementById()

Answer

A

– <imgsrc=”photo.jpg” alt=”” id=”lead-photo”>’
– var photo = document.getElementById(“lead-photo”);

Question 11

Q

getAttribute()

Answer

A

– <imgsrc=”stratocaster.jpg” alt=”electric guitar” id=”lead
image”>
– var bigImage = document.getElementById(“lead-image”);
– alert( bigImage.getAttribute(“src”) ); // Alerts
“stratocaster.jpg”.

Question 12

Q

getElementsByClassName()

Answer

A

– this allows you to access nodes in the document based
on the value of a class attribute.
* <div class="example">Element1</div>

<div>Element2</div>

<script>
const collection = document.getElementsByClassName("example");
 collection[0].innerHTML = "Hello World!";
</script>

Question 13

Q

Javascript 2 Flashcards

(13 cards)