Technique ARIA19:Using ARIA role=alert or Live Regions to Identify Errors

Example 1: Injecting error messages into a container with role=alert already present in the DOM

The following example uses role=alert which is equivalent to using aria-live=assertive.

In the example there is an empty error message container element with aria-atomic=true and an aria-live property or alert role present in the DOM on page load. The error container must be present in the DOM on page load for the error message to be spoken by most screen readers. aria-atomic=true is necessary to make Voiceover on iOS read the error messages after more than one invalid submission.

jQuery is used to test if the inputs are empty on submit and inject error messages into the live region containers if so. Each time a new submit is attempted the previous error messages are removed from the container and new error messages injected.

$(document).ready(function(e) {
  $('#signup').submit(function() {
    $('#errors').html('');
    if ($('#first').val() === '') {
      $('#errors').append('<p>Please enter your first name.</p>');
    }
    if ($('#last').val() === '') {
      $('#errors').append('<p>Please enter your last name.</p>');
    } 
    if ($('#email').val() === '') {
      $('#errors').append('<p>Please enter your email address.</p>');
    }
    return false;
  });
});
<form name="signup" id="signup">
  <p id="errors" role="alert" aria-atomic="true"></p>
  <div>
    <label for="first">First Name (required)</label><br>
    <input type="text" name="first" id="first">
  </div>
  <div>
    <label for="last">Last Name (required)</label><br>
    <input type="text" name="last" id="last">
  </div>
  <div>
    <label for="email">Email (required)</label><br>
    <input type="text" name="email" id="email">
  </div>
  <div>
    <input type="submit" name="button" id="button" value="Submit">
  </div>
 </form>

Working example: Using role=alert to identify errors.