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JavaScript

Posted by Kieran Barker
Kieran Barker
15,028 Points

What is wrong with this JavaScript code?

HTML:

<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <link href="css/normalize.css" rel="stylesheet">
    <title>A Clickable Button</title>
  </head>
  <body>
    <h1>A Clickable Button</h1>
    <button>Click Me!</button>
    <script src="js/script.js"></script>
  </body>
</html>

JavaScript:

const button = document.getElementsByTagName('button');
button.addEventListener('click', function() {
  alert('Yay! You clicked the button!');
});

Please can somebody tell me what I've done wrong?

1 Answer

Joel Bardsley
Joel Bardsley
31,258 Points
Joel Bardsley
Joel Bardsley
31,258 Points

Hi Kieran, you're very close!

getElementsByTagName() returns a HTMLCollection of elements with the given tag name.

In your case, as you only have one button element in your code, you can use button[0] to access that (the first) button element, and apply the event listener as follows:

button[0].addEventListener('click', function() {
  alert('Yay! You clicked the button!');
});

Hope that clears things up for you.

Kieran Barker
Kieran Barker
15,028 Points

Thanks, Joel -- just what I needed to know!