How can I add new array elements at the beginning of an array in Javascript?

Question

I have a need to add or prepend elements at the beginning of an array.

For example, if my array looks like below:

[23, 45, 12, 67]

Answer 1

If you want to push elements that are in a array at the beginning of you array use .apply(, ) :

const arr = [1, 2];
arr.unshift.apply(arr, [3, 4]);
console.log(arr); // [3, 4, 1, 2]