How do I fill an array in javascript?

Question

I have an array and I want to overwrite all values in it (that are all numbers) with a 0. So the array already exists.

I can do this with a for loop. However, is there a fill() call of some kind like the Java Arrays.fill()?

Answer 1

A very simple for-loop is all you need. There's no fill-function in JavaScript.

var length = arr.length,
for (var i = 0; i < length; i++) {
  arr[i] = 0;
}

Answer 2

You can use map for this.

var arr = [1,2,3];
arr = arr.map(function() {return 0});
//arr = [0, 0, 0]

The performance may be worse than a plain for loop.