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JavaScript Regular Expressions in JavaScript Validating a Form Form Validation

Now, use the test() method to test the string in text against the regular expression you just created. Remember the test

What am I doing wrong?

// Type inside this function
function isValidHex(text) {
  const hexRegEx = /^(#)[\da-f]{6}$/i
  test(text)  let hexRegEx = /^#[a-fA-F0-9]{6}$/;

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

Juan Luna Ramirez
Juan Luna Ramirez
9,038 Points

Not sure about the actual regExp itself but you have to return a value from the isValidHex function. The hexRegEx variable is a RegExp object which has the access to the test function. The test function returns a boolean so it makes sense to return that from the isValidHex function. Something like this:

function isValidHex(text) {
  const hexRegEx = /^(#)[\da-f]{6}$/i
  const isValid = hexRegEx.test(text) // true or false
  return isValid