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

Specification Status Comment
Unknown
The definition of 'ports' in that specification.
Unknown Initial definition

Browser compatibility

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari
Basic support 1 (Yes) 4.0 (2.0) 9 ? 10.0+
Feature Android Edge Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support ? (Yes) ? ? ? 3.0+

See also

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

Document Tags and Contributors

 Contributors to this page: chrisdavidmills
 Last updated by: chrisdavidmills,