BroadcastChannel: message event

The message event is fired on a BroadcastChannel object when a message arrives on that channel.

Bubbles No
Cancelable No
Interface MessageEvent
Event handler property onmessage

Examples

Live example

In this example there's a "sender" <iframe> that broadcasts the contents of a <textarea> when the user clicks a button. There are two "receiver" iframes that listen to the broadcast message and write the result into a <div> element.

Sender

const channel = new BroadcastChannel('example-channel');
const messageControl = document.querySelector('#message');
const broadcastMessageButton = document.querySelector('#broadcast-message');

broadcastMessageButton.addEventListener('click', () => {
    channel.postMessage(messageControl.value);
})

Receiver 1

const channel = new BroadcastChannel('example-channel');
channel.addEventListener('message', (event) => {
  received.textContent = event.data;
});

Receiver 2

const channel = new BroadcastChannel('example-channel');
channel.addEventListener('message', (event) => {
  received.textContent = event.data;
});

Result

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
message_event
54
≤79
38
No
41
preview
54
54
38
41
No
6.0

See also

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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/BroadcastChannel/message_event