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JavaScript JavaScript and the DOM (Retiring) Getting a Handle on the DOM Select a Page Element By Its ID

Jacob Kortbeek
Jacob Kortbeek
10,929 Points
Posted by Jacob Kortbeek
Jacob Kortbeek
10,929 Points

Select a Page Element By Its ID, addEventListener (Cannot read property 'addEventListener' of null)

I have copied the code from the video and i keep getting 'Cannot read property 'addEventListener' of null' what is wrong with my code?

<!DOCTYPE html>
<html>
  <head>
    <title>JavaScript and the DOM</title>
    <link rel="stylesheet" href="css/style.css">
  </head>
  <body>
    <h1 id="myHeading">JavaScript and the DOM</h1>
    <p>Making a web page interactive</p>
    <button id"myButton">make heading red</button>
    <script src="app.js"></script>
  </body>
</html>

const myHeading = document.getElementById('myHeading');

const myButton = document.getElementById('myButton');

myButton.addEventListener('click', () => {
  console.log('button clicked');
  myHeader.style.color = 'red';
});

2 Answers

Jeremiah Bushau
Jeremiah Bushau
24,061 Points

you're missing an equal sign when assigning the myButton ID in the HTML ;)

Jacob Kortbeek
Jacob Kortbeek
10,929 Points
Jacob Kortbeek
Jacob Kortbeek
10,929 Points

thanks its always the small things