1. Mozilla
  2. Add-ons
  3. Browser extensions
  4. JavaScript APIs
  5. events
  6. events.Event

events.Event

An object which allows the addition and removal of listeners for a browser event.

Type

Values of this type are objects.

Methods

events.Event.addListener()

Registers an event listener to an event.

events.Event.removeListener()

Deregisters an event listener from an event.

events.Event.hasListener()

Tests registration status of a listener.

events.Event.hasListeners()

Tests whether any listeners are registered to the event.

events.Event.addRules()

Registers rules to handle events.

events.Event.getRules()

Returns currently registered rules.

events.Event.removeRules()

Unregisters currently registered rules.

Browser compatibility

Chrome
Edge
Firefox
Opera
Safari
Firefox for Android
Safari on iOS
Event
Chrome – Full support
Chrome 21 (Release date: 2012-07-31)
footnote Full support
Edge – Full support
Edge 14 (Release date: 2016-08-02)
footnote Full support
Firefox – Full support
Firefox 53 (Release date: 2017-04-19)
footnote Full support
Opera – Full support
Opera 15 (Release date: 2013-07-02)
footnote Full support
Safari – Full support
Safari 14 (Release date: 2020-09-16)
footnote Full support
Firefox for Android – Full support
Firefox for Android 53 (Release date: 2017-04-19)
footnote Full support
Safari on iOS – Full support
Safari on iOS 15 (Release date: 2021-09-20)
footnote Full support
addListener
Chrome – Full support
Chrome 21 (Release date: 2012-07-31)
footnote Full support
Edge – Full support
Edge 14 (Release date: 2016-08-02)
footnote Full support
Firefox – Full support
Firefox 59 (Release date: 2018-03-13)
footnote Full support
Opera – Full support
Opera 15 (Release date: 2013-07-02)
footnote Full support
Safari – Full support
Safari 14 (Release date: 2020-09-16)
footnote Full support
Firefox for Android – Full support
Firefox for Android 59 (Release date: 2018-03-13)
footnote Full support
Safari on iOS – Full support
Safari on iOS 15 (Release date: 2021-09-20)
footnote Full support
addRules
Chrome – Full support
Chrome 21 (Release date: 2012-07-31)
footnote Full support
Edge – Full support
Edge 79 (Release date: 2020-01-15)
footnote Full support
Firefox – No support
Firefox
footnote No support
Opera – Full support
Opera 15 (Release date: 2013-07-02)
footnote Full support
Safari – No support
Safari
footnote No support
Firefox for Android – No support
Firefox for Android
footnote No support
Safari on iOS – No support
Safari on iOS
footnote No support
getRules
Chrome – Full support
Chrome 21 (Release date: 2012-07-31)
footnote Full support
Edge – Full support
Edge 79 (Release date: 2020-01-15)
footnote Full support
Firefox – No support
Firefox
footnote No support
Opera – Full support
Opera 15 (Release date: 2013-07-02)
footnote Full support
Safari – No support
Safari
footnote No support
Firefox for Android – No support
Firefox for Android
footnote No support
Safari on iOS – No support
Safari on iOS
footnote No support
hasListener
Chrome – Full support
Chrome 21 (Release date: 2012-07-31)
footnote Full support
Edge – Full support
Edge 14 (Release date: 2016-08-02)
footnote Full support
Firefox – Full support
Firefox 59 (Release date: 2018-03-13)
footnote Full support
Opera – Full support
Opera 15 (Release date: 2013-07-02)
footnote Full support
Safari – Full support
Safari 14 (Release date: 2020-09-16)
footnote Full support
Firefox for Android – Full support
Firefox for Android 59 (Release date: 2018-03-13)
footnote Full support
Safari on iOS – Full support
Safari on iOS 15 (Release date: 2021-09-20)
footnote Full support
hasListeners
Chrome – Full support
Chrome 21 (Release date: 2012-07-31)
footnote Full support
Edge – Full support
Edge 79 (Release date: 2020-01-15)
footnote Full support
Firefox – No support
Firefox
footnote No support
Opera – Full support
Opera 15 (Release date: 2013-07-02)
footnote Full support
Safari – No support
Safari
footnote No support
Firefox for Android – No support
Firefox for Android
footnote No support
Safari on iOS – No support
Safari on iOS
footnote No support
removeListener
Chrome – Full support
Chrome 21 (Release date: 2012-07-31)
footnote Full support
Edge – Full support
Edge 14 (Release date: 2016-08-02)
footnote Full support
Firefox – Full support
Firefox 59 (Release date: 2018-03-13)
footnote Full support
Opera – Full support
Opera 15 (Release date: 2013-07-02)
footnote Full support
Safari – Full support
Safari 14 (Release date: 2020-09-16)
footnote Full support
Firefox for Android – Full support
Firefox for Android 59 (Release date: 2018-03-13)
footnote Full support
Safari on iOS – Full support
Safari on iOS 15 (Release date: 2021-09-20)
footnote Full support
removeRules
Chrome – Full support
Chrome 21 (Release date: 2012-07-31)
footnote Full support
Edge – Full support
Edge 79 (Release date: 2020-01-15)
footnote Full support
Firefox – No support
Firefox
footnote No support
Opera – Full support
Opera 15 (Release date: 2013-07-02)
footnote Full support
Safari – No support
Safari
footnote No support
Firefox for Android – No support
Firefox for Android
footnote No support
Safari on iOS – No support
Safari on iOS
footnote No support

Tip: you can click/tap on a cell for more information.

Full support
No support

Note: This API is based on Chromium's chrome.events API. This documentation is derived from events.json in the Chromium code.

This page was last modified on by MDN contributors.

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