Web/API/MessageEvent/source

The source read-only property of the MessageEvent interface is a MessageEventSource (which can be a WindowProxy, MessagePort, or ServiceWorker object) representing the message emitter.

Syntax

let mySource = messageEvent.source;

Value

a MessageEventSource (which can be a WindowProxy, MessagePort, or ServiceWorker object) representing the message emitter.

Example

myWorker.onmessage = function(e) {
  result.textContent = e.data;
  console.log('Message received from worker');
  console.log(e.source);
};

Specifications

Specification	Status	Comment
HTML Living StandardThe definition of ' MessageEvent: source' in that specification.	Living Standard

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
source	Chrome Full support Yes	Edge Full support 12	Firefox Full support 55	IE No support No	Opera Full support Yes	Safari Full support Yes	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support 55	Opera Android Full support Yes	Safari iOS Full support Yes	Samsung Internet Android Full support Yes
Returns MessageEventSource	Chrome Full support Yes	Edge Full support ≤79	Firefox Full support 55	IE No support No	Opera ?	Safari ?	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support 55	Opera Android ?	Safari iOS ?	Samsung Internet Android Full support Yes

Legend

Full support  

Full support

No support  

No support

Compatibility unknown  

Compatibility unknown

See also

• ExtendableMessageEvent — similar to this interface but used in interfaces that needs to give more flexibility to authors.

MessageEvent.source by Mozilla Contributors is licensed under CC-BY-SA 2.5.