The HTML element represents a dialog box or other interactive component, such as a dismissible alert, inspector, or subwindow.
Attributes
This element includes the global attributes.
Warning: The tabindex attribute must not be used on the element.
open-
Indicates that the dialog is active and can be interacted with. When the
openattribute is not set, the dialog shouldn’t be shown to the user.
It is recommended to use the.show()or.showModal()methods to render dialogs, rather than theopenattribute. If ais opened using theopenattribute, it will be non-modal.
Accessibility considerations
The native HTML element should be used in creating modal dialogs as it provides usability and accessibility features that must be replicated if using other elements for a similar purpose. Use the appropriate .showModal() or .show() method to render dialogs. If creating a custom dialog implementation, ensure all expected default behaviors are supported and proper labeling recommendations are followed.
When implementing a dialog, it is important to consider the most appropriate place to set user focus. Explicitly indicating the initial focus placement by use of the autofocus attribute will help ensure initial focus is set to the element deemed the best initial focus placement for any particular dialog. When in doubt, as it may not always be known where initial focus could be set within a dialog, particularly for instances where a dialog’s content is dynamically rendered when invoked, then if necessary authors may decide focusing the element itself would provide the best initial focus placement. When using HTMLDialogElement.showModal() to open a , focus is set on the first nested focusable element.
Ensure a mechanism is provided to allow users to close a dialog. The most robust way to ensure all users can close a dialog is to include an explicit button to do so. For instance, a confirmation, cancel or close button as appropriate. Additionally, for those using a device with a keyboard, the Escape key is commonly expected to close modal dialogs as well. By default, a invoked by the showModal() method will allow for its dismissal by the Escape. A non-modal dialog does not dismiss via the Escape key by default, and depending on what the non-modal dialog represents, it may not be desired for this behavior. If multiple modal dialogs are open, Escape should only close the last shown dialog. When using , this behavior is provided by the browser.
The element is exposed by browsers similarly to custom dialogs using the ARIA role=”dialog” attribute. elements invoked by the showModal() method will have an implicit aria-modal=”true”, whereas elements invoked by the show() method, or rendered by use of the open attribute or changing the default display of a will be exposed as [aria-modal="false"]. When implementing modal dialogs, everything other than the and its contents should be rendered inert using the inert attribute. When using along with the HTMLDialogElement.showModal() method, this behavior is provided by the browser.
Usage notes
if they have the attributemethod="dialog"or if the button used to submit the form hasformmethod="dialog"set. In this case, the state of the form controls are saved, not submitted, thecloses, and thereturnValueproperty gets set to thevalueof the button that was used to save the form’s state.- The
::backdropCSS pseudo-element can be used to style the backdrop that is displayed behind aelement when the dialog is displayed withHTMLDialogElement.showModal(). For example, to dim unreachable content behind the modal dialog.
Examples
Simple example
The following will render a non-modal, or modal-less, dialog. The “OK” button allows the dialog to be closed when activated.
<dialog open>
<p>Greetings, one and all!p>
<form method="dialog">
<button>OKbutton>
form>
dialog>
Because this dialog was opened via the open attribute, it is non-modal. In this example, when the dialog is dismissed, no method is provided to re-open it. Opening dialogs via HTMLDialogElement.show() is preferred over the toggling of the boolean open attribute.
Advanced example
This example opens a modal dialog when the “Show the dialog” button is activated. The dialog contains a form. Updating the value of the updates the value of the “confirm” button.
HTML
<dialog id="favDialog">
<form method="dialog">
<p>
<label>Favorite animal:
<select>
<option value="default">Choose…option>
<option>Brine shrimpoption>
<option>Red pandaoption>
<option>Spider monkeyoption>
select>
label>
p>
<div>
<button value="cancel">Cancelbutton>
<button id="confirmBtn" value="default">Confirmbutton>
div>
form>
dialog>
<p>
<button id="showDialog">Show the dialogbutton>
p>
<output>output>
JavaScript
const showButton = document.getElementById('showDialog');
const favDialog = document.getElementById('favDialog');
const outputBox = document.querySelector('output');
const selectEl = favDialog.querySelector('select');
const confirmBtn = favDialog.querySelector('#confirmBtn');
showButton.addEventListener('click', () => {
favDialog.showModal();
});
selectEl.addEventListener('change', (e) => {
confirmBtn.value = selectEl.value;
});
favDialog.addEventListener('close', () => {
outputBox.value = `ReturnValue: ${favDialog.returnValue}.`;
});
Result
Note the JavaScript did not include the HTMLDialogElement.close() method. When a form in a dialog is submitted, if the method is dialog, the current state of the form is saved, not submitted, and the dialog gets closed.
It is important to provide a mechanism to close a dialog within the dialog element. For instance, the Esc key does not close non-modal dialogs by default, nor can one assume that a user will even have access to a physical keyboard (e.g., someone using a touch screen device without access to a keyboard).
Technical summary
Specifications
Browser compatibility
BCD tables only load in the browser
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