Core JavaScript

Sending and Receiving Worker Messages

This example demonstrates how to create a simple worker and send messages to it and receive messages from it.

WorkerMessaging.html

<!DOCTYPE html>
<html>
  <head>
    <title>XoaX.net's Javascript - Worker Messaging</title>
    <script type="text/javascript" src="WorkerMessaging.js"></script>
  </head>
  <body onload="Initialize()">
  	<p>Press F12 to see the logged messages.</p>
  </body>
</html>

WorkerMessaging.js

// Note this must be run from a web server
function Initialize() {
	var qWorker = new Worker("Worker.js");
	qWorker.onmessage = function(qEvent) {
		console.log("The main thread received the message: "+qEvent.data)
	}
	qWorker.postMessage("Hello from the main thread!");
}

Worker.js

onmessage = function(qEvent) {
	console.log("The worker received the message: "+qEvent.data);
	setTimeout("PostMessage()", 500);
}

function PostMessage() {
	postMessage("Hello from the worker!");
}
 

Output

 
 

© 2007–2025 XoaX.net LLC. All rights reserved.