Event

The Event interface represents any event which takes place in the DOM; some are user-generated (such as mouse or keyboard events), while others are generated by APIs (such as events that indicate an animation has finished running, a video has been paused, and so forth). There are many types of events, some of which use other interfaces based on the main Event interface. Event itself contains the properties and methods which are common to all events.

Interfaces based on Event

Below is a list of interfaces which are based on the main Event interface, with links to their respective documentation in the MDN API reference. Note that all event interfaces have names which end in "Event".

Constructor

Event()

Creates an Event object, returning it to the caller.

Properties

Event.bubbles Read only

A Boolean indicating whether the event bubbles up through the DOM or not.

Event.cancelBubble

A historical alias to Event.stopPropagation(). Setting its value to true before returning from an event handler prevents propagation of the event.

Event.cancelable Read only

A Boolean indicating whether the event is cancelable.

Event.composed Read only

A Boolean value indicating whether or not the event can bubble across the boundary between the shadow DOM and the regular DOM.

Event.currentTarget Read only

A reference to the currently registered target for the event. This is the object to which the event is currently slated to be sent; it's possible this has been changed along the way through retargeting.

Event.deepPath

An Array of DOM Nodes through which the event has bubbled.

Event.defaultPrevented Read only

Indicates whether or not event.preventDefault() has been called on the event.

Event.eventPhase Read only

Indicates which phase of the event flow is being processed.

Event.explicitOriginalTarget Read only

The explicit original target of the event (Mozilla-specific).

Event.originalTarget Read only

The original target of the event, before any retargetings (Mozilla-specific).

Event.returnValue

A non-standard alternative (from old versions of Microsoft Internet Explorer) to Event.preventDefault() and Event.defaultPrevented.

Event.scoped Read only

A Boolean indicating whether the given event will bubble across through the shadow root into the standard DOM. This property has been renamed to composed.

Event.srcElement

A non-standard alias (from old versions of Microsoft Internet Explorer) for Event.target.

Event.target Read only

A reference to the target to which the event was originally dispatched.

Event.timeStamp Read only

The time at which the event was created (in milliseconds). By specification, this value is time since epoch, but in reality browsers' definitions vary; in addition, work is underway to change this to be a DOMHighResTimeStamp instead.

Event.type Read only

The name of the event (case-insensitive).

Event.isTrusted Read only

Indicates whether or not the event was initiated by the browser (after a user click for instance) or by a script (using an event creation method, like event.initEvent)

Methods

Event.createEvent()

Creates a new event, which must then be initialized by calling its initEvent() method.

Event.initEvent()

Initializes the value of an Event created. If the event has already being dispatched, this method does nothing.

Event.preventBubble() Obsolete since Gecko 24

Prevents the event from bubbling. Obsolete, use event.stopPropagation instead.

Event.preventCapture() Obsolete since Gecko 24

Obsolete, use event.stopPropagation instead.

Event.preventDefault()

Cancels the event (if it is cancelable).

Event.stopImmediatePropagation()

For this particular event, no other listener will be called. Neither those attached on the same element, nor those attached on elements which will be traversed later (in capture phase, for instance)

Event.stopPropagation()

Stops the propagation of events further along in the DOM.

Event.getPreventDefault()

Non-standard. Returns the value of Event.defaultPrevented. Use Event.defaultPrevented instead.

Specifications

Browser compatibility

[1] Previous to Firefox 52, this property was defined on the UIEvent interface. See bug 1298970 for more details.

See also

• Types of events available: Event reference
• Comparison of Event Targets (target vs currentTarget vs relatedTarget vs originalTarget)
• Creating and triggering custom events
• For Firefox add-on developers:
  • Listening to events in Firefox extensions
  • Listening to events on all tabs