[javascript] Convert integer into its character equivalent, where 0 => a, 1 => b, etc

There you go: (a-zA-Z)

function codeToChar( number ) {
  if ( number >= 0 && number <= 25 ) // a-z
    number = number + 97;
  else if ( number >= 26 && number <= 51 ) // A-Z
    number = number + (65-26);
  else
    return false; // range error
  return String.fromCharCode( number );
}

input: 0-51, or it will return false (range error);

OR:

var codeToChar = function() {
  var abc = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ".split("");
  return function( code ) {
    return abc[code];
  };
})();

returns undefined in case of range error. NOTE: the array will be created only once and because of closure it will be available for the the new codeToChar function. I guess it's even faster then the first method (it's just a lookup basically).