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JavaScript Regular Expressions in JavaScript Validating a Form Form Validation

Aziz Kemal HOSCAN
.a{fill-rule:evenodd;}techdegree seal-36
Aziz Kemal HOSCAN
Full Stack JavaScript Techdegree Graduate 16,113 Points

Regexp problem

Answer to my solution is that; my solution is not an regexp object.

// Type inside this function
function isValidHex(text) {
  const hexRegEx = /^(£|#){1}[A-F0-9]{6}$/i.test(text);
  return hexRegEx;

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

Steven Parker
Steven Parker
227,140 Points

The regex expression is the part starting with the "/" and and ending with "/i". For task 2, you can invoke the method on "hexRegEx" as part of the return statement. Also:

  • you don't need an explicit repeat count for a single character
  • the token for a color is always "#", no matter what your country uses for currency
  const hexRegEx = /^#[A-F0-9]{6}$/i;