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
HTML Standard (HTML)
# dom-messageevent-source-dev

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
source
1
12
55
No
≤12.1
≤4
≤37
18
55
≤12.1
≤3
1.0
MessageEventSource_type
Yes
≤79
55
No
?
?
Yes
Yes
55
?
?
Yes

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/source