This setTimeout function only runs once and then stops. I get no errors so I have no idea why it's happening.

count = 100;

counter = setTimeout('timer()', 100);

$('#reset').click(function() {
    count = 100;
    counter = setTimeout('timer()', 100);
})

function timer() {
    if (count <= 0) {
        clearTimeout(counter);
        alert('done');
    }
    $('#counter').html(count);
    count -= 1;
}

I tried a few different formulations of the setTimeout function, including setTimeout(timer(),100) and setTimeout(function() { timer() }, 100)

This setTimeout function only runs once and then stops. I get no errors so I have no idea why it's happening.

count = 100;

counter = setTimeout('timer()', 100);

$('#reset').click(function() {
    count = 100;
    counter = setTimeout('timer()', 100);
})

function timer() {
    if (count <= 0) {
        clearTimeout(counter);
        alert('done');
    }
    $('#counter').html(count);
    count -= 1;
}

I tried a few different formulations of the setTimeout function, including setTimeout(timer(),100) and setTimeout(function() { timer() }, 100)

• javascript
• settimeout

• counter = setTimeout(timer, 100); is the preferred syntax – Brad M Commented Mar 4, 2013 at 22:28

6 Answers 6

You should be using setInterval() which repeats a function call, not setTimeout(), which does it once. Also, don't use () in function name reference.

var count = 100;

var counter = setInterval('timer', 100);

$('#reset').click(function() {
    count = 100;
    counter = setInterval('timer', 100);
})

function timer() {
    if (count <= 0) {
        clearInterval(counter);
        alert('done');
    }
    $('#counter').html(count);
    count -= 1;
}

setTimeout works correctly but it is not what you are looking for. try setInterval instead. setInteval(function, delay)

Yes, that's what setTimeout does. It runs the code once.

You want to use the setInterval method to run the code repeatedly.

setTimeout() - executes a function, once, after waiting a specified number of milliseconds.

You probably would like to go for setInterval() which executes a function, over and over again, at specified time intervals.

Not sure what you're trying to achieve, and I don't understand the $('#reset').click (etc) constructs. Are these JQuery?

However, why not use setInterval()? And then clear the interval timer when your condition is met?

var count = 10;

function counter() {

    if ( count > 0 )
    {
        --count;
        var t2 = setTimeout( counter, 1000 );

        document.querySelector("#demo").innerHTML = count;
    }
    else
    {
        clearTimeout(t2);

        document.querySelector("#demo").innerHTML = "Done";
    }
}

var countdown_timeout = counter();

<p>Count: <b><span id="demo"></span></b></p>