String.fromCharCode(yourIntegerValue)

var letters = 'ABCDEFGH';
for (var i = 0; i < letters.length; i++) {
   console.log(letters[i] + "=" + letters.charCodeAt(i))。
}
var number = 72;
console.log(number + " character code is=" + String.fromCharCode(number));

node fileName.js. 

PS C:\Users\Amit\javascript-code> node demo265.js
A=65
B=66
C=67
D=68
E=69
F=70
G=71
H=72
72 character code is=H