having a slightly weird issue that I cant figure out. Ive set up a javascript timer, all it does is repeats an interval every second that checks the difference between 2 dates and displays the results. All seems fine, however when leaving the browser open for several minutes (not touching it.. literally walking away for a while), it seems to "time out" and stop functioning. No console error messages or anything, the code just stops executing.. Was wondering if anyone had any idea what could be causing this? Is my code the issue or is this a built in browser function to stop js functions if there is no input from the user on a page for a certain time?
edit sorry should mention this timer is set to run for around 40 days at the moment so it will never realistically meet the clearinterval statement in a user session. The future date variable im adding to the function is a dynamic unix timestamp from PHP for a date which is roughly 40 days in future. Currently set to 1444761301.88
function MModeTimer(futureDate) {
zIntervalActive = true;
var currentTime = new Date().getTime() / 1000;
var timeRemaining = futureDate - currentTime;
var minute = 60;
var hour = 60 * 60;
var day = 60 * 60 * 24;
var zDays = Math.floor(timeRemaining / day);
var zHours = Math.floor((timeRemaining - zDays * day) / hour);
var zMinutes = Math.floor((timeRemaining - zDays * day - zHours * hour) / minute);
var zSeconds = Math.floor((timeRemaining - zDays * day - zHours * hour - zMinutes * minute));
if (zSeconds <= 0 && zMinutes <= 0) {
console.log("timer in negative");
// timer at zero
clearInterval(zTimeInterval);
} else {
if (futureDate > currentTime) {
console.log("timer interval running");
// changes html as part of function
}
}
}
zTimeInterval = setInterval(function() {
MModeTimer(zNewTime)
}, 1000);
This line:
clearInterval(zTimeInterval);
Is clearing the interval when the condition:
if (zSeconds <= 0 && zMinutes <= 0) {
Is met.
And as per the log you've wrote inside, that would be wrong. You are checking that zSeconds and zMinues are less or equal to 0. So when both are 0, the interval will be cleared.
Edit
As per your edits and explanations, may I suggest adding a console log that i'ts not inside any condition?:
function MModeTimer(futureDate) {
console.log('running');
//... rest of your code
That way you can make sure if the interval is running, maybe your conditions are not being TRUE after a while and you won't see any log, but the interval would be still running.
Related
I am trying to fix one time and that time is current time + 10 minutes and i wanted to use a condition where when the current time is equal to the set time it will run my logic is it possible?
I have tried using moment but not able to completely solve the problem
here is my tried solution
const currentTime = momentTz().tz("Asia/Kolkata");
console.log(currentTime.valueOf());
const notificationTime = momentTz()
.tz("Asia/Kolkata")
.add(10, "minutes")
.valueOf();
// console.log(currentTime);
console.log(notificationTime);
// i want to run in this way
if(notificationTime === currentTime.valueof())
{
//notiifcation send}
How will code come to know to run script after some time?
You should use setTimeout for this
Like
setTimeout(() => {
// your code which has to be executed after 10 minutes
}, 1000 * 60 * 10)
Or if you want check after some intervals you can use setInterval
Like following code will check for condition after every minute
var myInterval = setInterval(() => {
const currentTime = momentTz().tz("Asia/Kolkata");
if (notificationTime <= currentTime.valueof()) {
//notiifcation send
clearInterval(myInterval)
}
}, 1000 * 60)
I am trying to update a web-page at every tenth minute 7:40...7:50, etc. How do I do this?
Here is my code:
<body onload="checkTime()">
function checkTime(){
var unixTime = Date.now() / 1000;
var partTenMinuteTime = unixTime%600;
var time = unixTime - partTenMinuteTime + 600;
var difference = (time-unixTime)*10000;
console.log(difference);
setInterval(location.reload(),15000)
}
This is all I have, everything else I have tried does not work. I am using location.reload();
My problem is where this function gets called and how to implement it.
Here you can get nearest 10th min
let getRoundedDate = (minutes, d=new Date()) => {
let ms = 1000 * 60 * minutes; // convert minutes to ms
let roundedDate = new Date(Math.round(d.getTime() / ms) * ms);
return roundedDate
}
console.log(getRoundedDate(10))
Now you can use setInterval or in recursive setTimeout
You can get the minutes of the current hour and check how many minutes there are until the next 10-minute mark and use setTimeout. Your updatePage method should also continue to use call itself with setTimeout, if you are using AJAX to refresh the page (which makes more sense than reloading).
function updatePage(){
//update page
setTimeout(updatePage, 10 * 60 * 1000);
}
const now = new Date;
const nextDate = new Date;
nextDate.setFullYear(now.getFullYear());
nextDate.setDate(now.getDate());
nextDate.setMonth(now.getMonth());
nextDate.setHours(now.getHours());
nextDate.setMinutes(Math.ceil(now.getMinutes()/10)*10);
setTimeout(updatePage, nextDate - now);
You were very close with the solution in your question.
A couple of things to note:
You don't need setInterval(), but can use setTimeout() instead. After the page is reloaded, you will get a new timeout.
The callback you pass to setInterval() or setTimeout() needs to be a function and not a function call. If you include a function call, it will be executed immediately and not wait for the timeout or interval.
There is no need to create additional intervals to be able to correctly determine the 10 minute mark, as proposed in other answers to this question. You can correctly determine the correct time to call the reload action by doing the calculation you had in your question.
I'm aware that there are situations where you have too little control over the server code to be able to convert to AJAX, but if possible AJAX or websocket solutions should be preferred over reloading the page.
function reloadAfter(minutes) {
const millisToWait = minutes * 60 * 1000;
const millisLeft = millisToWait - (Date.now() % millisToWait);
setTimeout(() => location.reload(), millisLeft);
}
addEventListener('load', () => reloadAfter(10));
Why reload the page at all? Just use AJAX to query what you need. Here's code you could use to do your AJAX query, or reload the page... the later being a bad practice:
function onTenMin(func){
const m = 600000;
let i = setTimeout(()=>{
func(i); i = setInterval(()=>{
func(i);
}, m);
}, m-Date.now()%m);
}
addEventListener('load', ()=>{
onTenMin(interval=>{ // if you want you can pass the interval here
const dt = new Date;
console.log(dt.toString());
});
}); // end load
Just pass the function you want to onTenMin.
What's happening here?
Date.now() gives you milliseconds since January 1, 1970, 00:00:00 UTC. 600000 milliseconds is 10 minutes. % is the remainder operator, so it gives you the milliseconds remaining after division of the 600000. 600000 minus that remainder gives you how many more milliseconds until the next ten minute time. When that timeout happens it executes the function you pass to func then sets an interval which executes every 600000 milliseconds, passing the interval to func.
You can use a meta refresh instead don't burden the engine with timers
<meta http-equiv="refresh" content="600">
10 minutes = 600 seconds, so... This would automatically refresh your page every 10 minutes exactly.
Update
Every Exact 10th Minute Of An Hour
var tick = 10*60*1000,
tock = tick - Date.now() % tick;
setTimeout( "location.reload()", tock );
var tick = 10 * 60 * 1000,
tock = tick - Date.now() % tick;
setTimeout("location.reload()", tock);
//-----show something on the page----
with(new Date(tock))
document.write("Reloading in: " +
getMinutes() + " min, " +
getSeconds() + " sec, " +
getMilliseconds() + " mil."
);
I've been given a task to display multiple timers on a page in a table. The start values for these timers are stored in a database and loaded into the view when the page loads.
I initially designed this as a single timer. In that version, using the clearInterval() method to stop the timer from counting down past 0:00 works. With the multiple timers, it does not.
There's no way for me to anticipate how many records are going to display in the table.
The single counter variable was how I implemented this when there was only one timer. That seems to still work to start the countdown process, but doesn't stop it as expected when the clearInterval(counter) is called.
var counter;
// NOTE: Does not support days at this time
// Ex: StartTimer(5, 'm', 'timer') for Five Minutes
// Ex: StartTimer(5, 'h', 'timer') for Five Hours
function StartCountdownTimer(timeDistance, timeMeasurement, timerCallback) {
// Add timeDistance in specified measurement to current time
var countDownDate = moment().add(timeDistance, timeMeasurement).toDate();
var timeRemaining;
counter = setInterval(function () {
// Get Current Time
var now = new Date().getTime();
// Find the distance between now an the count down date
var distance = countDownDate - now;
let duration = moment.duration(distance * 1000, "milliseconds");
let hours = duration.hours();
let minutes = duration.minutes();
let seconds = duration.seconds();
if (minutes < 10 && hours && hours > 0) {
minutes = "0" + minutes;
}
if (seconds < 10) {
seconds = "0" + seconds;
}
// If the count down is finished clear the counter interval.
if (distance < 0) {
clearInterval(counter);
}
else {
timerCallback(hours, minutes, seconds);
}
}, 1000);
}
I would guess that the clearInterval() is not working because there are multiple timers on the page, but I'm not sure of the best way to load multiple variables and assign them to their own setInterval() function to then leverage when doing the clearInterval() later.
This is a separate JS file that is called by the HTML in the $(document).ready() function.
Any ideas on how to get this clearInterval() to work with multiple timers on a page?
Put the various intervals in an object, with a counter variable that increments every time you assign an interval. Then use the counter as the key and assign its value to the interval.
I'm working on a project on Node.js. I want to execute some conditional code portion after waiting for five minutes since the last code does. I only need it to run once that way (not everyday or ...). The rest of the code will take over but when it ticks five minute, that will execute. Can I accomplish this?
EDIT: The code from Abdennour TOUMI partially works. But his way of denoting the minute by the variable didn't work for me. So I made the following edit according to the example from the module's page.
var schedule = require('node-schedule');
var AFTER_5_MIN=new Date(new Date(new Date().getTime() + 5*60000))
var date = new Date(AFTER_5_MIN);
var j = schedule.scheduleJob(date, function() {
if(condition1){
// Runned once --> Thus, you need to cancel it
// code here, than code to run once
j.cancel();
}else{
//it will be repeated
}
});
Your mistake is use 5 fields & the right is 6 fields .
* 0 * * * * --> For each hour at the 0 minute of that hour.
To start after 5 minutes , you could calculate the minute of hour after 5 minutes :
var schedule = require('node-schedule');
var AFTER_5_MIN=new Date(new Date(new Date().getTime() + 5*60000)).getMinutes();
var j = schedule.scheduleJob(`* ${AFTER_5_MIN} * * * *`, function() {
if(condition1){
// Runned once --> Thus, you need to cancel it
// code here, than code to run once
j.cancel();
}else{
//it will be repeated
}
});
Is there any reason you can't use setTimeout()?
const WAIT_TIME = (60 * 5) * 1000; //5 Minutes
var timer = setTimeout(function(){
console.log('Cron job works!')
}, WAIT_TIME);
/*
* If conditions change in this five minutes and you need to cancel executing
* the callback above, you can clear the timer
* clearTimeout(timer);
*/
How can I write a script to detect when a user changes their system time in JS?
There is no (portable) way to track a variable in JavaScript. Also, date information does not lie in the DOM, so you don't get the possibility of a DOM event being triggered.
The best you can do is to use setInterval to check periodically (every second?). Example:
function timeChanged(delta) {
// Whatever
}
setInterval(function timeChecker() {
var oldTime = timeChecker.oldTime || new Date(),
newTime = new Date(),
timeDiff = newTime - oldTime;
timeChecker.oldTime = newTime;
if (Math.abs(timeDiff) >= 5000) { // Five second leniency
timeChanged(timeDiff);
}
}, 500);
Check in an interval function that the time has not changed too much:
function getTime() {
var d = new Date();
return d.getTime();
}
function checkTime() {
if (Math.abs(getTime() - oldtime) > 2000) { // Changed by more than 2 seconds?
alert("You changed the time!");
}
oldtime = getTime();
}
var oldtime = getTime();
setInterval(checkTime, 1000); // Check every second that the time is not off
Tested on Windows with Opera & FF and works flawlessly.
Don't think there is a solution to what you are asking for but you can get the users timezone offset.
new Date().getTimezoneOffset() * -1
This returns the offset in minutes from GMT. Bare in mind though this does not take DST into consideration.
var last_time = new Date().getTime();
setInterval(function() {
var time = new Date().getTime();
var offset = time - last_time;
if(offset < 0 || offset > 1500) {
// Time has been changed
}
last_time = time;
}, 1000);
In theory, this should work. It will check every second to make sure the time hasn't been changed. Note that I use 1100 milliseconds as most JS interpreters don't fire off events at exactly the time specified.
Hope this helps!
use performance.now() to get duration, which will be independent of system clock
see https://developer.mozilla.org/en-US/docs/Web/API/Performance/now
var t0 = performance.now();
doSomething();
var t1 = performance.now();
console.log("Call to doSomething took " + (t1 - t0) + " milliseconds.");
And then you can compare performance.now() elapsed with Date.now() elapsed to see whether they are diff too much.
Do you mean if they are changing their own system time to something that is wrong? You can ask the user for their time zone and get the correct time from the server, and then compare it to the user's system time.
You could check every 30 seconds, etc. If the new Time is off by more than 30 seconds +/- some threshold, you could do a more exhaustive comparison to determine how much it has been changed.