Sometimes, we want to find the number of occurrences a given value has in an array with JavaScript.
In this article, we’ll look at how to find the number of occurrences a given value has in an array with JavaScript.
How to find the number of occurrences a given value has in an array with JavaScript?
To find the number of occurrences a given value has in an array with JavaScript, we use the array filter
method.
For instance, we write
const dataset = [2, 2, 4, 2, 6, 4, 7, 8];
const search = 2;
const occurrences = dataset.filter((val) => {
return val === search;
}).length;
console.log(occurrences);
to call datset.filter
with a callback that checks if val
in dataset
is the same as search
and return an array where all the values are equal to search
.
Then we get the length
property to get the number of items equal to search
.
Conclusion
To find the number of occurrences a given value has in an array with JavaScript, we use the array filter
method.