How to insert a new element at any position of a JS array?

Question

I have an array [a, b, c]. I want to be able to insert a value between each elements of this array like that: [0, a, 0, b, 0, c, 0].

I guess it would be something like this, but I can't make it works.

for (let i = 0; i < array.length; i++) {     newArray = [         ...array.splice(0, i),         0,         ...array.splice(i, array.length),     ]; } 

Thank you for helping me!

Answer 1

Another way if you want to exclude the start and end of array is :

var arr = ['a', 'b', 'c']  var newArr = [...arr].map((e, i) => i < arr.length - 1 ? [e, 0] : [e]).reduce((a, b) => a.concat(b))    console.log(newArr)

Answer 2

For getting a new array, you could concat the part an add a zero element for each element.

var array = ['a', 'b', 'c'],      result = array.reduce((r, a) => r.concat(a, 0), [0]);        console.log(result);

Using the same array

var array = ['a', 'b', 'c'],      i = 0;    while (i <= array.length) {      array.splice(i, 0, 0);      i += 2;  }    console.log(array);

A bit shorter with iterating from the end.

var array = ['a', 'b', 'c'],      i = array.length;    do {      array.splice(i, 0, 0);  } while (i--)    console.log(array);