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JavaScript Regular Expressions in JavaScript Validating a Form Form Validation

Posted by Kelinia Johnson
Kelinia Johnson
10,189 Points

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?

app.js 
// 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)";
  }
});
index.html 
<!DOCTYPE html>
<html>

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

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

</html>

2 Answers

Juan Luna Ramirez
Juan Luna Ramirez
9,038 Points
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
}