Convert letter to number in JavaScript

Question

I would like to know how to convert each alphabetic character entered to a number.

e.g. a=1, b=2 ,c=3 up to z=26

In C I had managed to do something similar, by taking a character input and displaying it as an integer. But I'm not sure how I would do this in JavaScript.

Answer 1

var alphabet = ["a","b","c","d","e","f","g","h","i","j","k","l","m","n","o","p","q","r","s","t","u","v","w","x","y","z"];
var letter = "h";
var letterPosition = alphabet.indexOf(letter)+1;

EDIT:

Possibility to calculate the letters inside a string, aa=2, ab=3 etc.

function str_split(string, split_length) {
  //  discuss at: http://phpjs.org/functions/str_split/
  // original by: Martijn Wieringa
  // improved by: Brett Zamir (http://brett-zamir.me)
  // bugfixed by: Onno Marsman
  //  revised by: Theriault
  //  revised by: Rafał Kukawski (http://blog.kukawski.pl/)
  //    input by: Bjorn Roesbeke (http://www.bjornroesbeke.be/)
  //   example 1: str_split('Hello Friend', 3);
  //   returns 1: ['Hel', 'lo ', 'Fri', 'end']

  if (split_length == null) {
    split_length = 1;
  }
  if (string == null || split_length < 1) {
    return false;
  }
  string += '';
  var chunks = [],
    pos = 0,
    len = string.length;
  while (pos < len) {
    chunks.push(string.slice(pos, pos += split_length));
  }

  return chunks;
}


function count(string){
    var alphabet = ["a","b","c","d","e","f","g","h","i","j","k","l","m","n","o","p","q","r","s","t","u","v","w","x","y","z"];

    var splitted_string = str_split(string);

    var count = 0;
    for (i = 0; i < splitted_string.length; i++) { 
        var letterPosition = alphabet.indexOf(splitted_string[i])+1;
        count = count + letterPosition;
    }
    return count;
}

console.log(count("az")); // returns 27 in the console