Search code examples
javascripthtmlweb-worker

Use of setTimeout() in creating web worker in html5

I am following a tutorial on web worker at - http://www.w3schools.com/html/html5_webworkers.asp

Most of the things are clear to me but I don't know what is the purpose of using setTimeout function and how postMessage(i) is returning the value of i to w.onmessage.

Code - 

var i = 0;

function timedCount() {
    i = i + 1;
    postMessage(i);
    setTimeout("timedCount()",500);
}

timedCount();

Can anyone please explain me the flow how this example is working ?

Solution

  • The purpose of setTimeout is to call timedCount after 500 ms. Since it is called recursively, the effect is that timedCount is called twice in each second.

    Note also, that this would do the same:

    var i = 0;

function timedCount() {
    i = i + 1;
    postMessage(i);
}

setInterval(timedCount, 500);