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

Vasco Ramalho
Vasco Ramalho
1,998 Points
Posted by Vasco Ramalho
Vasco Ramalho
1,998 Points

document.querrySelectorAll

selection methods

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>
js/app.js 
let listItems = document.querySelectorAll("rainbow");
const colors = ["#C2272D", "#F8931F", "#FFFF01", "#009245", "#0193D9", "#0C04ED", "#612F90"];

for(var i = 0; i < colors.length; i ++) {
  listItems[i].style.color = colors[i];    
}

2 Answers

Sean T. Unwin
Sean T. Unwin
28,690 Points
Sean T. Unwin
Sean T. Unwin
28,690 Points

querySelector and querySelectoryAll parameters need to be prefaced with a dot (.) for classes and a hash (#) for an id. If the parameter is not prefaced with one of those characters then the function will assume a tag is given.

Furthernore, you want to be accessing the list items, as opposed to the list as whole, i.e. ('ul').

In this case, we can use querySelectorAll with li as the parameter. Now, in a real scenario we don't necessarily want to grab all the li elements in the page. This takes us back to the first point I made -- use the id selector + rainbow then a space and finally the tags to grab. This is exactly the same way we could select the same elements in CSS.

Don't forget to enclose it with quotes as the function takes a String.

Dan Weru
Dan Weru
47,649 Points
Dan Weru
Dan Weru
47,649 Points 
let listItems = document.querySelectorAll("#rainbow");
const colors = ["#C2272D", "#F8931F", "#FFFF01", "#009245", "#0193D9", "#0C04ED", "#612F90"];

for(var i = 0; i < colors.length; i++) {
  listItems[i].style.color = colors[i];    
}

To select elements with an id, use the # (hash) sign infront of the selector. Also there is no space between i and ++.

Sean T. Unwin
Sean T. Unwin
28,690 Points
Sean T. Unwin
Sean T. Unwin
28,690 Points

Not to detract from your answer, but the space after the i is provided by the challenge and is valid, in that it will be parsed correctly.