HTMLDialogElement: requestClose() method

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

The requestClose() method of the HTMLDialogElement interface requests to close the <dialog>. An optional string may be passed as an argument, updating the returnValue of the dialog.

This method differs from the HTMLDialogElement.close() method in that it fires a cancel event before firing the close event. Authors can call Event.preventDefault() in the handler for the cancel event to prevent the dialog from closing.

This method exposes the same behavior as the dialog's internal close watcher.

Syntax

requestClose()
requestClose(returnValue)

Parameters

returnValue Optional: A string representing an updated value for the HTMLDialogElement.returnValue of the dialog.

Return value

None (undefined).

Examples

Using requestClose()

The following example shows a simple button that, when clicked, opens a <dialog> containing a form, via the showModal() method. Once open you can click the X button to request to close the dialog (via the HTMLDialogElement.requestClose() method), or submit the form via the Confirm button.

HTML

html

<!-- Simple pop-up dialog box, containing a form -->
<dialog id="favDialog">
  <form method="dialog">
    <button type="button" id="close" aria-label="close" formnovalidate>
      X
    </button>
    <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 type="reset">Reset</button>
      <button type="submit">Confirm</button>
    </menu>
  </form>
</dialog>

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

JavaScript

const updateButton = document.getElementById("updateDetails");
const closeButton = document.getElementById("close");
const dialog = document.getElementById("favDialog");

// Update button opens a modal dialog
updateButton.addEventListener("click", () => {
  dialog.showModal();
});

// Form close button requests to close the dialog box
closeButton.addEventListener("click", () => {
  dialog.requestClose("animalNotChosen");
});

function dialogShouldNotClose() {
  // Add logic to decide whether to allow the dialog to close.
  // Closing prevented by default
  return true;
}

dialog.addEventListener("cancel", (event) => {
  if (!event.cancelable) return;
  if (dialogShouldNotClose()) {
    console.log("Closing prevented");
    event.preventDefault();
  }
});

If the "X" button was of type="submit", the dialog would have closed without requiring JavaScript. A form submission closes the <dialog> it is nested within if the form's method is dialog, so no "close" button is required.

Result

Specifications

Specification
HTML # dom-dialog-requestclose