How to insert a character at a given position of a string?

Question

How to insert a character at a given position of a string?

Ex: I have the string "abcdefg" and I want to add , before the "f" to stay "abcde,fg", how to do this?

Answer 1

Here’s an example of how to do this:

var a = "abcdefg";
var b = ",";
var position = 5;
var output = [a.slice(0, position), b, a.slice(position)].join('');
console.log(output);