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ExtendableMessageEvent: ExtendableMessageEvent() constructor - Web APIs | MDN
new ExtendableMessageEvent(type)
new ExtendableMessageEvent(type, options)
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.
const options = {
data: "hello message",
source: MessagePortReference,
ports: MessagePortListReference,
};
const myEME = new ExtendableMessageEvent("message", init);