Develop Reference

How do i make a javascript fuction repeat every few seconds? [duplicate]

I want repeat this code every 4 seconds, how i can do it with javascript or jquery easly ? Thanks. :)
$.get("request2.php", function(vystup){
if (vystup !== ""){
$("#prompt").html(vystup);
$("#prompt").animate({"top": "+=25px"}, 500).delay(2000).animate({"top": "-=25px"}, 500).delay(500).html("");
}
});

Use setInterval function
setInterval( fn , miliseconds )
From MDC docs:
Summary
Calls a function repeatedly, with a fixed time delay between each call to that function.
Syntax
var intervalID = window.setInterval(func, delay[, param1, param2, ...]);
var intervalID = window.setInterval(code, delay);
where
intervalID is a unique interval ID you can pass to clearInterval().
func is the function you want to be called repeatedly.
code in the alternate syntax, is a string of code you want to be executed repeatedly. (Using this syntax is not recommended for the same reasons as using eval())
delay is the number of milliseconds (thousandths of a second) that the setInterval() function should wait before each call to func. As with setTimeout, there is a minimum delay enforced.
Note that passing additional parameters to the function in the first syntax does not work in Internet Explorer.
Example
// alerts "Hey" every second
setInterval(function() { alert("Hey"); }, 1000);

setInterval(function(){
// your code...
}, 4000);

It's not too hard in javascript.
// declare your variable for the setInterval so that you can clear it later
var myInterval;
// set your interval
myInterval = setInterval(whichFunction,4000);
whichFunction{
// function code goes here
}
// this code clears your interval (myInterval)
window.clearInterval(myInterval);
Hope this helps!

Another possibility is to use setTimeout, but place it along with your code in a function that gets called recursively in the callback to the $.get() request.
This will ensure that the requests are a minimum of 4 seconds apart since the next request will not begin until the previous response was received.
// v--------place your code in a function
function get_request() {
$.get("request2.php", function(vystup){
if (vystup !== ""){
$("#prompt").html(vystup)
.animate({"top": "+=25px"}, 500)
.delay(2000)
.animate({"top": "-=25px"}, 500)
.delay(500)
.html("");
}
setTimeout( get_request, 4000 ); // <-- when you ge a response, call it
// again after a 4 second delay
});
}
get_request(); // <-- start it off

const milliseconds = 4000
setInterval(
() => {
// self executing repeated code below
}, milliseconds);

Call a Javascript function every 2 second continuously for 20 second.
var intervalPromise;
$scope.startTimer = function(fn, delay, timeoutTime) {
intervalPromise = $interval(function() {
fn();
var currentTime = new Date().getTime() - $scope.startTime;
if (currentTime > timeoutTime){
$interval.cancel(intervalPromise);
}
}, delay);
};
$scope.startTimer(hello, 2000, 10000);
hello(){
console.log("hello");
}

How to wait (for 2 seconds) after the completion of function?

I have javascript function which executes and after the execution i want to wait for 2 seconds. Is it possible in Javascript or not.
My Question is different. I want to wait after function gets executed or completed its execution not for till the function executes.
Javascript function
function ajax_closeCall(onDone) {
// alert("Close Call invoked.");
closeCall_onDone = onDone;
var closeCallUrl = soapUrl + "?action=closeCall&parentSessionId=" + parentSessionId;
closeCall_http_request = getNewHttpRequest('text/plain');
closeCall_http_request.onreadystatechange = callback_ajax_closeCall;
// http_request.open("POST", soapUrl, true);
closeCall_http_request.open("GET", closeCallUrl, true);
closeCall_http_request.send(null);
}
function callback_ajax_closeCall() {
if (closeCall_http_request.readyState != 4) {
return;
}
if (closeCall_http_request.status == 200) {
if (closeCall_onDone) {
closeCall_onDone();
}
stopMonitorCallState();
ajax_getCallState();
} else {
// there was a problem with the request,
// for example the response may be a 404 (Not Found)
// or 500 (Internal Server Error) response codes
alert(getLabel("cmmm_error_closecallfailed"));
}
}
After the above function executes, wait for 2 seconds.
How to achieve this scenario.

You wrap the code in a setTimeout:
setTimeout(function() {
// do your thing!
}, 2000);

you can use setInterval
setInterval(function(){
// write down your function that would you want to call after 2 seconds
}, 2000);

setTimeout gives you asynchronous wait time. for a function.
If you want to halt everything for two second. You can use the following trivial solution :
var date = new Date();var i;
for (i = date.getTime(); i<= date.getTime() + 2000; i = (new Date()).getTime()){/*Do Nothing*/}

Try this
call a function and then setTimeOut
function someFunction() //caller
{
one(); //call function one which will call second function from it
setTimeout(function()
{
//wait for 2 secs, do nothing
}, 2000);
}
// two functions after which you want to wait for 2 secs
function one()
{
two(); //it will call the second function
}
function two()
{
}

there is setTimeout function
setTimeout(function,milliseconds,param1,param2,...)
and you could use also setInterval function also
setInterval(function, milliseconds);

setTimeout functionality is not working

I am trying to use the jQuery setTimeout in order to call a method each x time interval:
$('.text').blur(function () {
doSmth();
});
$('.text').bind("paste", function (e) {
setTimeout(function () {
doSmth();
}, 5);
});
The timeout is not working , please advice !

What do you mean with "it's not working"?Anyway setTimeout() is a Javascript function that triggers only once after the specified interval.
If you wan't to trigger something every five second you should do:
var interval = setInterval(doSmth, 5000);
Where doSmth is a function defined elsewhere and 5000 is the number of millisecond of the interval. If yo want to stop the execution just do:
clearInterval(interval);

First, it isn't a "jQuery setTimeout". setTimeout is part of the native API, not jQuery's API.
Second, I assume you want 5 seconds. Currently you're doing 5 milliseconds.
$('.text').bind("paste", function(e) {
setTimeout(function() {
doSmth();
}, 5000);
});
The duration of 5 in your code is far too short to be perceptible.

I see that the other answers user setInterval, but from what I've read, you should avoid using setInterval, since you can end up with a stack of not-yet-executed function calls etc.
So what you could do instead is something like this:
var myTimeout;
$('.text').bind("paste", function (e) {
function loopFunction () {
doSmth();
myTimeout = setTimeout(loopFunction, 5000);
}
myTimeout = setTimeout(loopFunction, 5000);
});
Now you have a function that calls itself every five seconds.

According to your feedback,here is the solution:
var interval = setInterval(doSmth, 5000);
$('.text').blur(function() {
doSmth();
});
$('.text').bind("paste", function(e) {
setTimeout(function() {
doSmth();
}, 0);
});
Thanks for you amazing support.

setTimeout and setInterval not working

I want to be able to call the function work() every 6 seconds. My jQuery code is
function looper(){
// do something
if (loopcheck) {
setInterval(work,6000);
}
else {
console.log('looper stopped');
}
}
The problem I am running into is that it loops over work twice quickly, and then it will wait for 6 seconds. i tried using setTimeout with similar results.
What could be causing work to be called twice before the delay works?

setInterval should be avoided. If you want work to be repeatedly called every 6 seconds, consider a recursive call to setTimeout instead
function loopWork(){
setTimeout(function () {
work();
loopWork();
}, 6000);
}
Then
function looper(){
// do something
if (loopcheck) {
loopWork()
}
else {
console.log('looper stopped');
}
}
And of course if you ever want to stop this, you'd save the value of the last call to setTimeout, and pass that to clearTimeout
var timeoutId;
timeoutId = setTimeout(function () {
work();
loopWork();
}, 6000);
Then to stop it
clearTimeout(timeoutId);

Use old-style setTimeout()
var i=0;
function work(){
console.log(i++);
}
function runner(){
work();
setTimeout(runner, 6000);
}
runner();

I prefer the following pattern myself I find it easier to follow:
function LoopingFunction() {
// do the work
setTimeout(arguments.callee, 6000); // call myself again in 6 seconds
}
And if you want to be able to stop it at any point:
var LoopingFunctionKeepGoing = true;
function LoopingFunction() {
if(!LoopingFunctionKeepGoing) return;
// do the work
setTimeout(arguments.callee, 6000); // call myself again in 6 seconds
}
Now you can stop it at any time by setting LoopingFunctionKeepGoing to false.

Calling a function every 60 seconds

Using setTimeout() it is possible to launch a function at a specified time:
setTimeout(function, 60000);
But what if I would like to launch the function multiple times? Every time a time interval passes, I would like to execute the function (every 60 seconds, let's say).

If you don't care if the code within the timer may take longer than your interval, use setInterval():
setInterval(function, delay)
That fires the function passed in as first parameter over and over.
A better approach is, to use setTimeout along with a self-executing anonymous function:
(function(){
// do some stuff
setTimeout(arguments.callee, 60000);
})();
that guarantees, that the next call is not made before your code was executed. I used arguments.callee in this example as function reference. It's a better way to give the function a name and call that within setTimeout because arguments.callee is deprecated in ecmascript 5.

use the
setInterval(function, 60000);
EDIT : (In case if you want to stop the clock after it is started)
Script section
<script>
var int=self.setInterval(function, 60000);
</script>
and HTML Code
<!-- Stop Button -->
Stop

A better use of jAndy's answer to implement a polling function that polls every interval seconds, and ends after timeout seconds.
function pollFunc(fn, timeout, interval) {
var startTime = (new Date()).getTime();
interval = interval || 1000;
(function p() {
fn();
if (((new Date).getTime() - startTime ) <= timeout) {
setTimeout(p, interval);
}
})();
}
pollFunc(sendHeartBeat, 60000, 1000);
UPDATE
As per the comment, updating it for the ability of the passed function to stop the polling:
function pollFunc(fn, timeout, interval) {
var startTime = (new Date()).getTime();
interval = interval || 1000,
canPoll = true;
(function p() {
canPoll = ((new Date).getTime() - startTime ) <= timeout;
if (!fn() && canPoll) { // ensures the function exucutes
setTimeout(p, interval);
}
})();
}
pollFunc(sendHeartBeat, 60000, 1000);
function sendHeartBeat(params) {
...
...
if (receivedData) {
// no need to execute further
return true; // or false, change the IIFE inside condition accordingly.
}
}

In jQuery you can do like this.
function random_no(){
var ran=Math.random();
jQuery('#random_no_container').html(ran);
}
window.setInterval(function(){
/// call your function here
random_no();
}, 6000); // Change Interval here to test. For eg: 5000 for 5 sec
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div id="random_no_container">
Hello. Here you can see random numbers after every 6 sec
</div>

setInterval(fn,time)
is the method you're after.

You can simply call setTimeout at the end of the function. This will add it again to the event queue. You can use any kind of logic to vary the delay values. For example,
function multiStep() {
// do some work here
blah_blah_whatever();
var newtime = 60000;
if (!requestStop) {
setTimeout(multiStep, newtime);
}
}

Use window.setInterval(func, time).

A good example where to subscribe a setInterval(), and use a clearInterval() to stop the forever loop:
function myTimer() {
}
var timer = setInterval(myTimer, 5000);
call this line to stop the loop:
clearInterval(timer);

Call a Javascript function every 2 second continuously for 10 second.
var intervalPromise;
$scope.startTimer = function(fn, delay, timeoutTime) {
intervalPromise = $interval(function() {
fn();
var currentTime = new Date().getTime() - $scope.startTime;
if (currentTime > timeoutTime){
$interval.cancel(intervalPromise);
}
}, delay);
};
$scope.startTimer(hello, 2000, 10000);
hello(){
console.log("hello");
}

function random(number) {
return Math.floor(Math.random() * (number+1));
}
setInterval(() => {
const rndCol = 'rgb(' + random(255) + ',' + random(255) + ',' + random(255) + ')';//rgb value (0-255,0-255,0-255)
document.body.style.backgroundColor = rndCol;
}, 1000);
<script src="test.js"></script>
it changes background color in every 1 second (written as 1000 in JS)

// example:
// checkEach(1000, () => {
// if(!canIDoWorkNow()) {
// return true // try again after 1 second
// }
//
// doWork()
// })
export function checkEach(milliseconds, fn) {
const timer = setInterval(
() => {
try {
const retry = fn()
if (retry !== true) {
clearInterval(timer)
}
} catch (e) {
clearInterval(timer)
throw e
}
},
milliseconds
)
}

here we console natural number 0 to ......n (next number print in console every 60 sec.) , using setInterval()
var count = 0;
function abc(){
count ++;
console.log(count);
}
setInterval(abc,60*1000);

I see that it wasn't mentioned here if you need to pass a parameter to your function on repeat setTimeout(myFunc(myVal), 60000); will cause an error of calling function before the previous call is completed.
Therefore, you can pass the parameter like
setTimeout(function () {
myFunc(myVal);
}, 60000)
For more detailed information you can see the JavaScript garden.
Hope it helps somebody.

I favour calling a function that contains a loop function that calls a setTimeout on itself at regular intervals.
function timer(interval = 1000) {
function loop(count = 1) {
console.log(count);
setTimeout(loop, interval, ++count);
}
loop();
}
timer();

There are 2 ways to call-
setInterval(function (){ functionName();}, 60000);
setInterval(functionName, 60000);
above function will call on every 60 seconds.