Sometimes, we want to find index of all occurrences of element in array with JavaScript.
In this article, we’ll look at how to find index of all occurrences of element in array with JavaScript.
How to find index of all occurrences of element in array with JavaScript?
To find index of all occurrences of element in array with JavaScript, we can use the array map method.
For instance, we write
const indices = array.map((e, i) => (e === value ? i : "")).filter(String);
to call array.map to return all the indices of all the items in array that’s equal to value.
If entry e equals value, then we return the index i of it.
Then we call filter with string to filter out any non-number entries.
Conclusion
To find index of all occurrences of element in array with JavaScript, we can use the array map method.
