Web/API/ExtendableMessageEvent/ExtendableMessageEvent

The ExtendableMessageEvent() constructor creates a new ExtendableMessageEvent object instance.

Syntax

var extendableMessageEvent = new ExtendableMessageEvent(type, init);

Parameters

type

A DOMString that defines the type of the message event being created.

init Optional

An initialisation object, which should contain the following parameters:

data

• The event's data — this can be any data type.
• origin: A DOMString that defines the origin of the corresponding service worker's environment settings object.
• lastEventId: A DOMString that defines the last event ID of the event source.
• source: The Client, ServiceWorker or MessagePort that sent the message.
• ports: An array containing the MessagePort objects connected to the channel sending the message.

Examples

var init = {
             data : 'hello message',
             source : MessagePortReference,
             ports : MessagePortListReference
           }

var myEME = new ExtendableMessageEvent('message', init);

Specifications

Specification	Status	Comment
Service WorkersThe definition of 'ExtendableMessageEvent()' in that specification.	Working Draft	Initial definition.

Browser compatibility

The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
ExtendableMessageEvent() constructor Experimental'	Chrome ?	Edge ?	Firefox Full support 45 Notes' Full support 45 Notes' Notes' Extended Support Releases (ESR) before Firefox 78 ESR do not support service workers and the Push API.	IE No support No	Opera ?	Safari No support No	WebView Android No support No	Chrome Android ?	Firefox Android Full support 45	Opera Android ?	Safari iOS No support No	Samsung Internet Android ?

Legend

Full support  

Full support

No support  

No support

Compatibility unknown  

Compatibility unknown

Experimental. Expect behavior to change in the future.'

Experimental. Expect behavior to change in the future.

See implementation notes.'

See implementation notes.

See also

• Using Service Workers
• Service workers basic code example
• Is ServiceWorker ready?
• Channel Messaging

ExtendableMessageEvent() by Mozilla Contributors is licensed under CC-BY-SA 2.5.