<!DOCTYPE html> <html> <body> <p>Count numbers: <output id="result"></output></p> <button onclick="startWorker()">Start Worker</button> <button onclick="stopWorker()">Stop Worker</button> <p><strong>Note:</strong> Internet Explorer 9 and earlier versions do not support Web Workers.</p> <script> var w; function startWorker() { if(typeof(Worker) !== "undefined") { if(typeof(w) == "undefined") { w = new Worker("demo_workers.js"); } w.onmessage = function(event) { document.getElementById("result").innerHTML = event.data; }; } else { document.getElementById("result").innerHTML = "Sorry, your browser does not support Web Workers..."; } } function stopWorker() { w.terminate(); w = undefined; } </script> </body> </html>