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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
11,790 Points
John Johnson
John Johnson
11,790 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');