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

Lilly Brown
Lilly Brown
7,097 Points

I am unsure of how to answer this, please can you give me some advice?

This is where I have got to:

var listItems = document.getElementById('rainbow'); var colors = ["#C2272D", "#F8931F", "#FFFF01", "#009245", "#0193D9", "#0C04ED", "#612F90"];

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

js/app.js
var listItems = document.getElementById('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

Jonathan Grieve
MOD
Jonathan Grieve
Treehouse Moderator 91,252 Points

What's happening is you want to loop through a collection of selected element but by its nature getElementById() only selects one instance of an element. Element ID attributes identify a unique element.

You can use a method that selects multiple elements in much the same way that CSS Selectors do.

Good ones to use include

  • getElementsByClassName()
  • getElementsByTagName()
  • querySelectorAll()

You should then be able to loop through all the selected elements.