How to split an array into smaller arrays every time a specific value appears JavaScript?

Question

How would you go about splitting an array at the word 'split' and creating smaller sub arrays out of them?

This is what my array looks like right now (but much longer):

const myArray = ['abc', 'xyz', 123, 'split', 'efg', 'hij', 456, 'split'];

This is what I would like it to look like:

const newArray =[['abc', 'xyz', 123], ['efg', 'hij', 456]];

If it helps at all I also have the indexes of the words 'split' in an array like this:

const splitIndex = [3, 7];

Please show your attempt, and what the problem is with it. – trincot Jan 17 '22 at 18:12 — trincot, Jan 17 '22 at 18:12

score 3 · Accepted Answer · answered Jan 17 '22 at 18:14

You could iterate splitIndex and slice the array until this index.

const
    data = ['abc', 'xyz', 123, 'split', 'efg', 'hij', 456, 'split'],
    splitIndex = [3, 7],
    result = [];

let i = 0;

for (const j of splitIndex) {
    result.push(data.slice(i, j));
    i = j + 1;
}

console.log(result);

score 0 · Answer 2 · answered Jan 17 '22 at 18:19

const myArr = ['abc', 'xyz', 123, 'split', 'efg', 'hij', 456, 'split'];

const foo = (arr, key) => {
    let temp = [];
    const result = [];
    arr.forEach(v => {
        if (v !== key) {
            temp.push(v);
        } else {
            result.push(temp);
            temp = [];
        }
    })
    return result;
}
console.log(foo(myArr, 'split'));

output:

[ [ 'abc', 'xyz', 123 ], [ 'efg', 'hij', 456 ] ]

How to split an array into smaller arrays every time a specific value appears JavaScript?

2 Answers2