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How to Clear setInterval() without Knowing the ID

By Sam Deering

JavaScript

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Problem
Declaring a setInterval() without keeping a reference to it (which is returned from the function call setInterval(), it returns an id number for the registered event).

Like so:

var interval = setInterval(function() {
    console.log('i');
}, 1000);
console.log(interval);

It you can see it assigns a random number as the id for the event. Then when we clear the interval it uses that id.

Simply by calling:

clearInterval(interval);

A Diirty Solution
Now this is not good coding practice (for a number of reasons) but if you really need to clear that interval we can simply do a loop to find the id of the event to stop all setInterval() events that are running. I’ve done a quick jsfiddle to show you. https://jsfiddle.net/WqCws/.

for(i=0; i<100; i++)
{
    window.clearInterval(i);
}

I’m pretty sure this will also work for setTimeout() and clearTimeout();

Sam Deering has 15+ years of programming and website development experience. He was a website consultant at Console, ABC News, Flight Centre, Sapient Nitro, and the QLD Government and runs a tech blog with over 1 million views per month. Currently, Sam is the Founder of Crypto News, Australia.

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