Peter Lubbers - Pro HTML 5 Programming

Using Timers
CHAPTER 8 ■ USING THE HTML5 WEB WORKERS API
Although HTML5 Web Workers cannot access the window object, they can make use of the full JavaScript
timing API, typically found on the global window:
var t = setTimeout(postMessage, 2000, "delayed message");
Simple Example Code
For completeness, Listings 9-2 and 9-3 show the code for the simple page and the Web Worker
JavaScript file.
Listing 8-2. Simple HTML Page that calls an HTML5 Web Worker
Simple HTML5 Web Workers Example
Simple HTML5 Web Workers Example
Your browser does not support HTML5 Web Workers.
Stop Task
Post a Message
function stopWorker() {
worker.terminate();
}
function messageHandler(e) {
console.log(e.data);
}
function errorHandler(e) {
console.warn(e.message, e);
}
function loadDemo() {
if (typeof(Worker) !== "undefined") {
document.getElementById("support").innerHTML =
"Excellent! Your browser supports HTML5 Web Workers";
worker = new Worker("echoWorker.js");
worker.addEventListener("message", messageHandler, true);
worker.addEventListener("error", errorHandler, true);
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