Develop Reference

Changer SetInterval Values After Interval

If I can try to make everyone understand what I am looking for, I am looking for the value of the interval to change to lets say "5000ms" after "1000ms" and then it would go on to the next value such as "2000ms" and repeat all over again! The current code I have is pretty much a stopwatch, It adds the number 1 to a paragraph every 1000ms. Any help is extremely appreciated!
<script>
function myFunction() {
clicks += 1;
}
setInterval(myFunction, 1000);
var clicks = 0;
function myFunction() {
clicks += 1;
document.getElementById("demo").innerHTML = clicks;
// connects to paragraph id
}
</script>
<p id="demo"></p>
<!--connects to getElementById-->

Don't use setInterval - this functions will perform the action in any given interval, which you set once.
Use setTimeout instead. Which performs the action only once after given interval, and then call it again and again with different interval values.

what about this
<script>
var clicks = 0;
myFunction(1000);
function myFunction( currentInterval ) {
clicks ++;
document.getElementById("demo").innerHTML = clicks;
if ( currentInterval == 1000 )
{
currentInterval = 5000;
}
else if ( currentInterval == 5000 )
{
currentInterval = 2000;
}
else
{
currentInterval = 1000;
}
setTimeout( function(){ myFunction( currentInterval ) }, currentInterval );
}
</script>
<p id="demo"></p>

you should try using recursive timeout instead of interval
var timeout = 1000;
var timer;
function startTimer() {
clearTimeout(timer);
timer = setTimeout(function() {
console.log('tick');
startTimer();
}, timeout);
}
startTimer();
// timeout = 2000
// timeout = 500
// clearTimeout(timer); to cancel
<script src="https://getfirebug.com/firebug-lite-debug.js"></script>

This might look a little complicated but you can try something like this:
JSFiddle.
(function() {
var interval = null;
var limit = 5;
function initInterval(callback, index) {
var msToSec = 1000;
if (interval) {
clearInterval();
}
console.log("Delay: ", index)
interval = setInterval(callback, index * msToSec);
}
function clearInterval() {
window.clearInterval(interval);
interval = null;
}
function resetInterval(callback, count) {
clearInterval();
initInterval(callback, count);
}
function main() {
var count = 1;
var notify = function() {
console.log("Hello World: ", count);
var _nextCount = ((count++) % limit) + 1;
if (count < 10) {
resetInterval(notify, _nextCount);
} else {
console.log("Stoping loop...");
clearInterval();
}
}
initInterval(notify, count);
}
main()
})()

Break while loop with timer?

I was wondering is it possible to break a while loop with a timer?
looked on the internet but could not find a solution for it.
while (true) {
alert('hi');
} if (timer < 0) {
timer?
document.write('Time is up!');
break;
}
Thank you.

You should use setTimeout for this.
var timer = 3;
setTimeout(excuteMethod, 1000);
function excuteMethod() {
alert(timer + ' call');
timer--;
if (timer >= 0) setTimeout(excuteMethod, 1000);
}
Demo : http://jsfiddle.net/kishoresahas/9s9z7adt/

I'm not sure if this is the correct approach, but it works,
(function() {
var delay = 30;
var date = new Date();
var timer = date.setTime(date.getTime() + delay);
var count = 0;
function validate() {
var now = new Date();
if (+now > timer)
return false;
else
return true;
}
while (true) {
count++;
console.log(count);
if (!validate()) {
console.log("Time expired");
break;
}
// Fail safe.
if (count > 50000) {
console.log("Count breached")
break;
}
}
})()

You can change control value in timer function and break the loop.
var control = true;
while(control)
{
...
}
setTimeout(function(){
control = false;
}, delay); //delay is miliseconds
Or based on counter
var control = true,
counter = 10;
while(control){
...
}
// you can handle as count down
// count down counter every 1000 miliseconds
// after 10(counter start value) seconds
// change control value to false to break while loop
// and clear interval
var counterInterval = setInterval(function(){
counter--;
if(counter == 0)
{
control = false;
clearInterval(counterInterval);
}
},1000);

Timed for loop in Javascript

I don't even know how to get started with this: I need a for loop that executes a function (say a simple console.log()) with a timed delay between each execution. I've been trying to do it with setTimeout() and it never works. If I call the function that has the loop from setTimeout, it won't work. Ideally I'd want my for loop to print something x times, with a couple of seconds delay between each printing. Any ideas how that might work? I've tried something like this:
function printStuff(){
for(var i=0;i<5;i++){
console.log(i);
}
};
setTimeout(printStuff(),1000);

For me you should execute setInterval and inside this you should increase counter. When counter reach the limit you simply clear interval.
var counter = 0;
var limit = 10;
var myVar = setInterval(function(){
if (counter > limit)
{
clearInterval(myVar);
}
counter++;
console.log("test");
}, 1000);

init();
function init() {
setTimeout(init, 2*1000); // wait 2 sec then call init again
console.log(Date());
}
Or use setInterval:
// Call init after 2 sec and repeat calling it every 2. sec
setInterval(init, 2*1000);
function init() {
console.log(Date());
}

You could use the async module.
var count = 0;
async.whilst(
function () { return count < 5; },
function (callback) {
count++;
console.log(count);
setTimeout(callback, 1000);
},
function (err) {
// 5 seconds have passed
}
);
This way the count will be printed every second

var i = 0;
function timeout(){
setTimeout(log, 1000);
}
function log(){
console.log(i++);
timeout();
}
log();
http://jsfiddle.net/sq4v0kbf/

Use setInterval() instead of setTimeout(). Parameters are just the same:
setInterval(function () {
// your utility code goes here
}, 2000);

Here is one more way to do it. Use a wrapper function.
var time = 2000;
for (var i = 0; i < 10; i++) {
(function (i) {
setTimeout(function () {
console.log(i);
}, time);
})(i);
time+=2000;
}

You can create a sort of delayed loop function with the number of iterations/times you want to run. Something like this:
var delayedLoop = function (n, milliseconds) {
var iteration = function (n) {
if (n > 0) {
n--;
console.log(n);
setTimeout(function () {
iteration(n)
}, milliseconds);
}
};
iteration(n);
}
delayedLoop(4, 1000);
You could even expand the idea and even passing a function to be executed each time.
See demo.

Here's what I think is simpler (and doesn't have the fallbacks of) than a setInterval
var limit = 10,
counter = 0,
delay = 1000;
function doIt() {
document.body.innerHTML += 'Hit counter: ' + (counter++) + '<br />';
if (counter < limit) {
setTimeout(doIt, delay);
}
}
doIt();
And you can generalize it
function runTimedLoop(delay, howMany, callback) {
var index = 0;
function iteration() {
callback(index++);
if (index < howMany) {
setTimeout(iteration, delay);
}
}
iteration();
}
runTimedLoop(1000, 10, function(index) {
document.body.innerHTML += 'Hit counter: ' + (index++) + '<br />';
});

javascript autoreload in infinite loop with time left till next reload

i need a JavaScript, that relaods a page every 30 seconds, and will show how much time there is until next reload at the ID time-to-update, Example:
<p>Refreshing in <span id="time-to-update" class="light-blue"></span> seconds.</p>
i also need it to repeat itself infinitely.
thank you for reading, i hope it helps not me but everyone else, and a real big thank you if you could make this script.

(function() {
var el = document.getElementById('time-to-update');
var count = 30;
setInterval(function() {
count -= 1;
el.innerHTML = count;
if (count == 0) {
location.reload();
}
}, 1000);
})();

A variation that uses setTimeout rather than setInterval, and uses the more cross-browser secure document.location.reload(true);.
var timer = 30;
var el = document.getElementById('time-to-update');
(function loop(el) {
if (timer > 0) {
el.innerHTML = timer;
timer -= 1;
setTimeout(function () { loop(el); }, 1000);
} else {
document.location.reload(true);
}
}(el));

http://jsfiddle.net/zGGEH/1/
var timer = {
interval: null,
seconds: 30,
start: function () {
var self = this,
el = document.getElementById('time-to-update');
el.innerText = this.seconds; // Output initial value
this.interval = setInterval(function () {
self.seconds--;
if (self.seconds == 0)
window.location.reload();
el.innerText = self.seconds;
}, 1000);
},
stop: function () {
window.clearInterval(this.interval)
}
}
timer.start();

countdown timer stops at zero i want it to reset

I am trying to figure out a way to make my countdown timer restart at 25 all over again when it reaches 0. I dont know what I am getting wrong but it wont work.
Javascript
window.onload = function() {
startCountDown(25, 1000, myFunction);
}
function startCountDown(i, p, f) {
var pause = p;
var fn = f;
var countDownObj = document.getElementById("countDown");
countDownObj.count = function(i) {
//write out count
countDownObj.innerHTML = i;
if (i == 0) {
//execute function
fn();
//stop
return;
}
setTimeout(function() {
// repeat
countDownObj.count(i - 1);
},
pause
);
}
//set it going
countDownObj.count(i);
}
function myFunction(){};
</script>
HTML
<div id="countDown"></div>

try this, timer restarts after 0
http://jsfiddle.net/GdkAH/1/
Full code:
window.onload = function() {
startCountDown(25, 1000, myFunction);
}
function startCountDown(i, p, f) {
var pause = p;
var fn = f;
var countDownObj = document.getElementById("countDown");
countDownObj.count = function(i) {
// write out count
countDownObj.innerHTML = i;
if (i == 0) {
// execute function
fn();
startCountDown(25, 1000, myFunction);
// stop
return;
}
setTimeout(function() {
// repeat
countDownObj.count(i - 1);
}, pause);
}
// set it going
countDownObj.count(i);
}
function myFunction(){};
​

I don't see you resetting the counter. When your counter goes down to 0, it executes the function and return. Instead, you want to execute the function -> reset the counter -> return
You can do this by simply adding i = 25 under fn() :
function startCountDown(i, p, f) {
var pause = p;
var fn = f;
var countDownObj = document.getElementById("countDown");
countDownObj.count = function(i) {
// write out count
countDownObj.innerHTML = i;
if (i == 0) {
// execute function
fn();
i = 25;
// stop
return;
}
setTimeout(function() {
// repeat
countDownObj.count(i - 1);
},
pause
);
}
// set it going

in #Muthu Kumaran code is not showing zero after countdown 1 . you can update to this:
if (i < 0) {
// execute function
fn();
startCountDown(10, 1000, myFunction);
// stop
return;
}

The main reason for using setInterval for a timer that runs continuously is to adjust the interval so that it updates as closely as possible to increments of the system clock, usually 1 second but maybe longer. In this case, that doesn't seem to be necessary, so just use setInterval.
Below is a function that doesn't add non–standard properties to the element, it could be called using a function expression from window.onload, so avoid global variables altogether (not that there is much point in that, but some like to minimise them).
var runTimer = (function() {
var element, count = 0;
return function(i, p, f) {
element = document.getElementById('countDown');
setInterval(function() {
element.innerHTML = i - (count % i);
if (count && !(count % i)) {
f();
}
count++;
}, p);
}
}());
function foo() {
console.log('foo');
}
window.onload = function() {
runTimer(25, 1000, foo);
}