Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

JavaScript JavaScript and the DOM (Retiring) Getting a Handle on the DOM Selecting Multiple Elements

Posted by Arvind Krishna
Arvind Krishna
3,550 Points

What is the correct method?

is querySelectorAll the right one to use?

js/app.js 
var listItems = document.querySelectorAll['#rainbow'];
var colors = ["#C2272D", "#F8931F", "#FFFF01", "#009245", "#0193D9", "#0C04ED", "#612F90"];

for(var i = 0; i < colors.length; i ++) {
  listItems[i].style.color = colors[i];    
}
index.html 
<!DOCTYPE html>
<html>
  <head>
    <title>Rainbow!</title>
  </head>
  <body>
    <ul id="rainbow">
      <li>This should be red</li>
      <li>This should be orange</li>
      <li>This should be yellow</li>
      <li>This should be green</li>
      <li>This should be blue</li>
      <li>This should be indigo</li>
      <li>This should be violet</li>
    </ul>
    <script src="js/app.js"></script>
  </body>
</html>

1 Answer

John Johnson
John Johnson
11,789 Points
John Johnson
John Johnson
11,789 Points

Firstly, querySelectorAll is a method. Even if you're trying to make a list, you will always use parenthesis () on methods, not square brackets []. The method querySelectorAll() will automatically make a list out of all of the elements it finds using the CSS selector you give it.

Then, you just need the proper CSS syntax. You'll want to target every item that is a <li> element under the <ul id='rainbow>. You can do this with either the child selector or the descendant selector.

Descendant Selector:

var listItems = document.querySelectorAll('#rainbow li');

Child Selector:

var listItems = document.querySelectorAll('#rainbow > li');