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A MessageEvent is the interface representing a message received by a target, being a WebSocket or a WebRTC RTCDataChannel

The action triggered by this event is set via an event handler set on WebSocket.onmessage or RTCDataChannel.onmessage.

Note: This feature is available in Web Workers.


Creates a new MessageEvent.


This interface also inherits properties from its parent, Event. Read only
Returns a DOMString, Blob or an ArrayBuffer containing the data send by the emitter.
Is a DOMString


This interface also inherits methods from its parent, Event.

Do not use this anymore: use the MessageEvent() constructor instead.

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support ? 4.0 (2.0)[1] ? ? ?
Feature Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support ? ? ? ? ?

[1] As of Gecko 11.0 (Firefox 11.0 / Thunderbird 11.0 / SeaMonkey 2.8), Gecko supports ArrayBuffer for data, but not Blob.

See also

Document Tags and Contributors

 Last updated by: Sebastianz,