Tryit Editor v2.7

Edit This Code:
<!DOCTYPE html>
<html>
<body>

<form>
  <fieldset id="myFieldset">
    <legend>Personalia:</legend>
    Name: <input type="text"><br>
    Email: <input type="text"><br>
    Date of birth: <input type="text">
  </fieldset>
</form><br>

<button onclick="disableField()">Disable fieldset</button>
<button onclick="undisableField()">Undisable fieldset</button>

<p><b>Note:</b> The disabled property of the Fieldset object is not supported in Internet Explorer and Safari.</p>

<script>
function disableField() {
    document.getElementById("myFieldset").disabled = true;
}

function undisableField() {
    document.getElementById("myFieldset").disabled = false;
}
</script>

</body>
</html>