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Change a Character in a string - setCharAt() Function

How do you change a character in a string in JavaScript? It's not possible! So I decided to make a small function to do it. In any other language, this code will work...

var str = 'Hello World';
str[4] = ',';
alert(str);//Shows 'Hell, World'

But not in javascript. So I have come up with a simple setCharAt function that will do this for you.

function setCharAt(str,index,chr) {
	if(index > str.length-1) return str;
	return str.substr(0,index) + chr + str.substr(index+1);
}
//Demo
var str = 'Hello World';
str = setCharAt(str,4,',');
alert(str);

The first argument(str) is the string in which the replacement must be made
The second argument(index) is the index of the character to be replaced
The third argument(chr) is the new character that should be inserted.

This method is a bit bulky. An alternative method is to extend the 'String' class using 'prototype'

String.prototype.setCharAt = function(index,chr) {
	if(index > this.length-1) return str;
	return this.substr(0,index) + chr + this.substr(index+1);
}
//Demo
var str = 'Hello World';
str = str.setCharAt(4,',');
alert(str);

A rather complicated way to do a simple thing. Am I missing something? Is there an easier way to do this?

Change a Character in a string - setCharAt() Function

Change a Character in a string - setCharAt() Function

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