How to Clear setInterval() without Knowing the ID

Sam Deering
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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. http://jsfiddle.net/WqCws/.

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

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

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  • ilan

    I solve it by creating a fake interval whose id number is apparently the highest one. This method is very important with working on userscripts.

    var fake=setInterval(“”);

    for(var i = 0 ; i < fake ; i++) {
    clearInterval(i);
    }