ExtendableMessageEvent.data

The data read-only property of the ExtendableMessageEvent interface returns the event's data. It can be any data type.

Syntax

var myData = extendableMessageEvent.data;

Value

Any data type.

Examples

When the following code is used inside a service worker to respond to a push messages by sending the data received via PushMessageData to the main context via a channel message, the event object of onmessage will be a ExtendableMessageEvent.

var port;

self.addEventListener('push', function(e) {
  var obj = e.data.json();

  if(obj.action === 'subscribe' || obj.action === 'unsubscribe') {
    port.postMessage(obj);
  } else if(obj.action === 'init' || obj.action === 'chatMsg') {
    port.postMessage(obj);
  }
});

self.onmessage = function(e) {
  console.log(e.data);
  port = e.ports[0];
}

Specifications

Specification Status Comment
Service Workers
The definition of 'ExtendableMessageEvent.data' in that specification.
Working Draft Initial definition.

Browser compatibility

DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
data
Experimental
Chrome Full support 51Edge Full support ≤79Firefox Full support 45
Notes
Full support 45
Notes
Notes Extended Support Releases (ESR) before Firefox 78 ESR do not support service workers and the Push API.
IE No support NoOpera ? Safari No support NoWebView Android No support NoChrome Android Full support 51Firefox Android Full support 45Opera Android ? Safari iOS No support NoSamsung Internet Android Full support 5.0

Legend

Full support
Full support
No support
No support
Compatibility unknown
Compatibility unknown
Experimental. Expect behavior to change in the future.
Experimental. Expect behavior to change in the future.
See implementation notes.
See implementation notes.

See also