HTMLDialogElement.open

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The open property of the HTMLDialogElement interface is a boolean value reflecting the open HTML attribute, indicating whether the dialog is available for interaction.

Syntax

dialogInstance.open = true;
var myOpenValue = dialogInstance.open;

Value

A boolean value representing the state of the open HTML attribute. true means it is set, and therefore the dialog is shown. false means it not set, and therefore the dialog is not shown.

The property is now read only — it is possible to set the value to programmatically show or hide the dialog.

Examples

The following example shows a simple button that, when clicked, opens a <dialog> containing a form via the showModal() method. From there you can click the Cancel button to close the dialog (via the HTMLDialogElement.close() method), or submit the form via the submit button.

  <!-- Simple pop-up dialog box, containing a form -->
  <dialog id="favDialog">
    <form method="dialog">
      <section>
        <p><label for="favAnimal">Favorite animal:</label>
        <select id="favAnimal" name="favAnimal">
          <option></option>
          <option>Brine shrimp</option>
          <option>Red panda</option>
          <option>Spider monkey</option>
        </select></p>
      </section>
      <menu>
        <button id="cancel" type="reset">Cancel</button>
        <button type="submit">Confirm</button>
      </menu>
    </form>
  </dialog>

  <menu>
    <button id="updateDetails">Update details</button>
  </menu>

  <script>
    (function() {
      var updateButton = document.getElementById('updateDetails');
      var cancelButton = document.getElementById('cancel');
      var dialog = document.getElementById('favDialog');
      dialog.returnValue = 'favAnimal';

      function openCheck(dialog) {
        if(dialog.open) {
          console.log('Dialog open');
        } else {
          console.log('Dialog closed');
        }
      }

      // Update button opens a modal dialog
      updateButton.addEventListener('click', function() {
        dialog.showModal();
        openCheck(dialog);
      });

      // Form cancel button closes the dialog box
      cancelButton.addEventListener('click', function() {
        dialog.close('animalNotChosen');
        openCheck(dialog);
      });

    })();
  </script>

Note: You can find this example on GitHub as htmldialogelement-basic (see it live also).

Specifications

Specification
HTML Standard (HTML) # dom-dialog-open

Browser compatibility

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	WebView Android	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet
`open`	37	79	53 See bug 840640.	No	24	No	37	37	53 See bug 840640.	24	No	3.0