MessageEvent.ports

The ports read-only property of the MessageEvent interface is an array of MessagePort objects 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).

Syntax

var myPorts = messageEvent.ports;

Value

An array of MessagePort objects.

Example

onconnect = function(e) {
  var port = e.ports[0];

  port.addEventListener('message', function(e) {
    var workerResult = 'Result: ' + (e.data[0] * e.data[1]);
    port.postMessage(workerResult);
  });

  port.start(); // Required when using addEventListener. Otherwise called implicitly by onmessage setter.
}

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
ports
1
12
4
9
Yes
4
≤37
Yes
Yes
Yes
3
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/ports