The MessageEvent() constructor creates a new MessageEvent object.
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MessageEvent: MessageEvent() constructor
Syntax
js
new MessageEvent(type)
new MessageEvent(type, options)
Parameters
-
type -
A string with the name of the event. It is case-sensitive and browsers always set it to
message. optionsOptional-
An object that, in addition of the properties defined in
Event(), can have the following properties:dataOptional-
The data you want contained in the MessageEvent. This can be of any data type, and will default to
nullif not specified. originOptional-
A string representing the origin of the message emitter. This defaults to an empty string (
'') if not specified. lastEventIdOptional-
A string representing a unique ID for the event. This defaults to an empty string ("") if not specified.
sourceOptional-
A
MessageEventSource(which can be aWindow, aMessagePort, or aServiceWorkerobject) representing the message emitter. This defaults tonullif not set. portsOptional-
An array of
MessagePortobjects representing the ports associated with the channel the message is being sent through where appropriate (E.g. in channel messaging or when sending a message to a shared worker). This defaults to an empty array ([]) if not specified.
Return value
A new MessageEvent object.
Examples
js
const myMessage = new MessageEvent("message", {
data: "hello",
});
Specifications
Browser compatibility
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Internet Explorer | Opera | Safari | WebView Android | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | |
MessageEvent |
16 | 14 | 26 | No | ≤12.1 | 6 | 4.4 | 18 | 26 | ≤12.1 | 6 | 1.0 |
See also
ExtendableMessageEvent— similar to this interface but used in interfaces that needs to give more flexibility to authors.
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https://developer.mozilla.org/en-US/docs/Web/API/MessageEvent/MessageEvent