JavaScript program to generate random string

Following program shows you how to generate random string.
This program gets string length from user and prints random string of the given length

var stringLength = prompt("Please enter the string length:")
var alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
var result = '';
for (var i = 1; i <= stringLength; i++) {
result = result + alphabet.charAt(Math.floor(Math.random() * alphabet.length))
}
console.log("Random string is: " + result);

Output:

Please enter the string length:
10
AwcNqKwhil