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JavaScript JavaScript Basics Hello, JavaScript! JavaScript Practice Challenge

Kurt Coleman
Kurt Coleman
2,967 Points
Posted by Kurt Coleman
Kurt Coleman
2,967 Points

document.querySelector("h1").textContent = "🔥BOOM!🔥";

This statement generates an error. TypeError: Cannot set property 'textContent' of null

Kurt Coleman
Kurt Coleman
2,967 Points
Kurt Coleman
Kurt Coleman
2,967 Points

I'm lost. Don't worry about it.

4 Answers

Cameron Childres
Cameron Childres
11,820 Points
Cameron Childres
Cameron Childres
11,820 Points

Do you have an <h1> element in your HTML? If it's not there then document.querySelector("h1") won't find anything to put your text in to.

Example that works:

<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
  </head>
  <body>
    <h1></h1>
    <script src="js/script.js"></script>
  </body>
</html>

document.querySelector("h1").textContent = "🔥BOOM!🔥";

I receive your same error when I remove the <h1> element:

<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
  </head>
  <body>
    <script src="js/script.js"></script>
  </body>
</html>
Sorin Chircu, SC OSF GLOBAL SERVICES SRL Calea Plevnei nr.159, Sector 6, 060014, Bucuresti. VAT: RO12900448
Sorin Chircu, SC OSF GLOBAL SERVICES SRL Calea Plevnei nr.159, Sector 6, 060014, Bucuresti. VAT: RO12900448
14,547 Points
Sorin Chircu, SC OSF GLOBAL SERVICES SRL Calea Plevnei nr.159, Sector 6, 060014, Bucuresti. VAT: RO12900448
Sorin Chircu, SC OSF GLOBAL SERVICES SRL Calea Plevnei nr.159, Sector 6, 060014, Bucuresti. VAT: RO12900448
14,547 Points

From what I've seem a problem can also appear if you add the <script> to the head, as it'll look for the <h1> element there, maybe that's the problem.

Muhammad Khan
PLUS
Muhammad Khan
Courses Plus Student 8,772 Points
Muhammad Khan
Muhammad Khan
Courses Plus Student 8,772 Points

I received the same error at line No. 10, but when I added the <h1></h1> tag in my HTML file, the error gone and the the program is running good and it gives the desired output. Thanks.

Kurt Coleman
Kurt Coleman
2,967 Points
Kurt Coleman
Kurt Coleman
2,967 Points

Yes. There was an <h1> element in the HTML. This line of code was supplied. I didn't write it. It generated an error. I looked for the H1 element first.

Cameron Childres
Cameron Childres
11,820 Points
Cameron Childres
Cameron Childres
11,820 Points

Would you mind sharing your code so I can have a closer look? You can copy and paste it here (using the markdown cheatsheet linked below the comment field to make it look pretty and easily readable) or take a snapshot from your workspace (camera icon in the top right) and post the URL it generates.