HTMLDialogElement.returnValue - Web APIs 编辑

Experimental

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

The returnValue property of the HTMLDialogElement interface gets or sets the return value for the <dialog>, usually to indicate which button the user pressed to close it.

Syntax

dialogInstance.returnValue = 'myReturnValue';
var myReturnValue = dialogInstance.returnValue;

Value

A DOMString representing the returnValue of the dialog.

Examples

The following example displays a button to open a <dialog> containing a form via the showModal() method. From there, either button will close the dialog.

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

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

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

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

      function handleUserInput(returnValue) {
        if (returnValue === 'Cancel' || returnValue == null) {
          // User canceled the dialog, do nothing
        } else if (returnValue === 'Confirm') {
          // User chose a favorite animal, do something with it
        }
      }

      // “Update details” button opens the <dialog> modally
      updateButton.addEventListener('click', function() {
        dialog.showModal();
        openCheck(dialog);
        handleUserInput(dialog.returnValue);
      });
    })();
  </script>

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

Specifications

Browser compatibility

BCD tables only load in the browser

See also

• The HTML element implementing this interface: <dialog>.