ExtendableMessageEvent: ExtendableMessageEvent() constructor

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since April 2018.

Note: This feature is only available in Service Workers.

The ExtendableMessageEvent() constructor creates a new ExtendableMessageEvent object.

Syntax

js
new ExtendableMessageEvent(type)
new ExtendableMessageEvent(type, options)

Parameters

type

A string with the name of the event. It is case-sensitive and browsers set it to messageerror or message.

options Optional

An object that, in addition of the properties defined in ExtendableEvent(), can have the following properties:

data Optional

The event's data; this can be any data type. It defaults to null.

origin Optional

A string that defines the origin of the corresponding service worker's environment settings object. It defaults to "".

lastEventId Optional

A string that defines the last event ID of the event source. It defaults to "".

source Optional

The Client, ServiceWorker or MessagePort that sent the message. It defaults to null.

ports Optional

An array containing the MessagePort objects connected to the channel sending the message. It defaults to an empty array.

Return value

A new ExtendableMessageEvent object.

Examples

js
const options = {
  data: "hello message",
  source: MessagePortReference,
  ports: MessagePortListReference,
};

const myEME = new ExtendableMessageEvent("message", init);

Specifications

Specification
Service Workers Nightly
# dom-extendablemessageevent-extendablemessageevent

Browser compatibility

desktop mobile
Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
ExtendableMessageEvent() constructor
Chrome – Full support
Chrome 51 (Release date: 2016-05-25)
footnote Full support
Edge – Full support
Edge 17 (Release date: 2018-04-30)
footnote Full support
Firefox – Full support
Firefox 44 (Release date: 2016-01-26)
footnote Full support
Opera – Full support
Opera 38 (Release date: 2016-06-08)
footnote Full support
Safari – Full support
Safari 11.1 (Release date: 2018-04-12)
footnote Full support
Chrome Android – Full support
Chrome Android 51 (Release date: 2016-06-08)
footnote Full support
Firefox for Android – Full support
Firefox for Android 44 (Release date: 2016-01-26)
footnote Full support
Opera Android – Full support
Opera Android 41 (Release date: 2016-10-25)
footnote Full support
Safari on iOS – Full support
Safari on iOS 11.3 (Release date: 2018-03-29)
footnote Full support
Samsung Internet – Full support
Samsung Internet 5 (Release date: 2016-12-15)
footnote Full support
WebView Android – Full support
WebView Android 51 (Release date: 2016-06-08)
footnote Full support
WebView on iOS – No support
WebView on iOS
footnote No support

Legend

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

Full support
Full support
No support
No support

See also