Most efficient way to create a zero filled JavaScript array?

Question

What is the most efficient way to create an arbitrary length zero filled array in JavaScript?

Answer 1

To create an all new Array

new Array(arrayLength).fill(0);

To add some values at the end of an existing Array

[...existingArray, ...new Array(numberOfElementsToAdd).fill(0)]

Example

//**To create an all new Array**

console.log(new Array(5).fill(0));

//**To add some values at the end of an existing Array**

let existingArray = [1,2,3]

console.log([...existingArray, ...new Array(5).fill(0)]);