create string of random characters

makerandomid.js

//make a random id with specified length, and get chars out of specified string
function makeid(length, string) {
	var text = "";
	
	//the list of chars to pick chars for id
	var possible = (string ? string : "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789");
	
	//iterate over every char, with default length of 8 characters
	while (text.length < (length ? length : 8)) {
		//add a random picked char from "possible"
		text += possible.charAt(Math.floor(Math.random() * possible.length));
	}
	
	return text;
}

this is used in my projectgreen project