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JavaScript Regular Expressions in JavaScript Validating a Form Form Validation

For this step of the challenge, write a regular expression that will match any hexadecimal string and store it in a vari

I honestly dont know what to do

// Type inside this function
function isValidHex(text) {

  const hexRegEx = /[#][A-F]{7}+/i;


const hex = document.getElementById("hex");
const body = document.getElementsByTagName("body")[0];

hex.addEventListener("input", e => {
  const text = e.target.value;
  const valid = isValidHex(text);
  if (valid) {
    body.style.backgroundColor = "rgb(176, 208, 168)";
  } else {
    body.style.backgroundColor = "rgb(189, 86, 86)";
<!DOCTYPE html>

    <title>DOM Manipulation</title>
<link rel="stylesheet" href="style.css" />

    <div id="content">
        <p>Enter a valid hex value below to make the screen turn green.</p>
        <input type="text" id="hex">
    <script src="app.js"></script>


1 Answer

Hi Kennedy,

these regular expressions can be really tricky indeed.

In your regular expression you did not check for digits, only for letters A-Z, So you want to include \d in there as well to check the numbers.

Another thing is it is 6 characters after the #, not 7. ;-)

And finally I would reccomend using the ^ at the beginning (= to start with) and $ for the end (= to end with).

Let me know if you still don't pass and I am happy to help further.

Blessings from Berlin and happy java-scripting, Nils

PS: If my answer helped you or solved your issues, please upvote my answer and/or mark it as "Best answer" (so people browsing the community forum know your issue is solved)