How do I replace a character at a particular index in JavaScript?

Question

I have a string, let\'s say Hello world and I need to replace the char at index 3. How can I replace a char by specifying a index?

var str = \"h         


        

Answer 1

var str = "hello world";
console.log(str);
var arr = [...str];
arr[0] = "H";
str = arr.join("");
console.log(str);