BroadcastChannel: postMessage() method

Baseline 2022

Newly available

Since March 2022, this feature works across the latest devices and browser versions. This feature might not work in older devices or browsers.

The BroadcastChannel.postMessage() sends a message, which can be of any kind of Object, to each listener in any browsing context with the same origin. The message is transmitted as a 'message' event targeted at each BroadcastChannel bound to the channel.

Note: This feature is available in Web Workers

Syntax

js
channel.postMessage(message)

Parameters

message

Data to be sent to the other window. The data is serialized using the structured clone algorithm. This means you can pass a broad variety of data objects safely to the destination window without having to serialize them yourself.

Return value

None.

Exceptions

InvalidStateError DOMException

Thrown if the BroadcastChannel has already been closed.

DataCloneError DOMException

Thrown if any part of the input data is not serializable.

Specifications

Specification
HTML Standard
# dom-broadcastchannel-postmessage-dev

Browser compatibility

BCD tables only load in the browser

See also