Using the setInterval() function in JavaScript

You can use the "setInterval()" function in JavaScript to make your code run repeatedly on a timer. This can be super useful for clocks, counters, updating your page with live data or even creating games.

To use this function, you supply it with a "handler function" which will contain your code that you wish to execute repeatedly. You also provide the function with a delay in milliseconds - which actually sets the interval.

In this video I take you through a straightforward example of the "setInterval()" function where we display a number on the page and for every second that passes, that number increases by 1. We also take a look at the "clearInterval()" function which has the ability to cancel a set-interval.

For your reference, check this out:

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[relkovic]

The sound of your keyboard is just beautiful.

[tt]

Nice one. Was scratching my head about setInterval but you have given a few pointers. Cheers.

[iliashterev]

Interesting, I did not know that clearInterval is keeping track of the numbers passed and it would go further instead of starting from zero again.
And so I thought that you will need to get the number from the timerText and re-assign it to count before continue.

You tutorial is very good. I am sorry that you are not having more likes. You deserve more.

[GerardSiebels]

Amazing! Best tutorial for setInterval I’ve seen! Thanks!

Simple and straightforward code, it solved my problem. Great tutorial!

[AsimYilan]

Thank u 4 this Video Tutorial. But i have a problem with:
When i click Start or Pause Button second time, i cant started oder paused again. Can u Help me?

[rafaelribeiro]

Hello, i have a problem when i try to run the code.
I can't run the code because he said "Cannot read property 'addEventListener' of null"
can u help me pls?
Thank you.

[sahadatsajib]

Thanks Domb,
But finally I face a new problem, when i pressed double or more click our start button, then this function didn't work properly (rapid counting), ,
so Man whats i can do, , ??🤔

[padmapriyavks]

If there are four side signal with two colours red and green. It want to be automatically rotate in clockwise using setinterval and clearinterval when green is on, others want to be red how can I do this. Can any one help me to do this?

[vaclavvlcek]

Thank you for this video, it helped me to understand that matter.

[Igor-vkfl]

But there is a problem. If you click multiple times on the "start timer" it will execute multiple times the function and the numbers start to get counting faster. Even if you click on "Pause timer the same amaount of imes you click on "start timer" it wont stop.

[alifsuria]

Can you show how to use parameter in setInterval()?

[acethomas]

Do you know how to do scripts for different functions for an online game I’ll give you an example javascript:setInterval(function()%7BStreetWarsRaidDialog.attack(0)%7D, 20), setInterval(function()%7BStreetWarsRaidDialog.attack(1)%7D, 20), setInterval(function()%7BStreetWarsRaidDialog.attack(2)%7D, 20), setInterval(function()%7BStreetWarsRaidDialog.attack(3)%7D, 20), setInterval(function()%7BStreetWarsRaidDialog.attack(4)%7D, 20); but there’s other things you can do on the game also that I don’t know how to write a JavaScript for them I just need help on it if at all possible

[MusicEffekt]

please record with a larger font size so that the codes are more readable on screen. Thanks

[chvishnu]

Sir please provide 120 seconds time kill JavaScript