Solve Caesers Cipher Using a switch code in Javascript

Question

You may be familiar with caeser cipher(see this wiki on caesers cipher AKA ROT13)

I have been looking at solutions for the cipher but I do not see anyone using a switch statement. Given the challenge (see below), can this problem be simply solved by using a switch statement? I have put my code below but it does not work.

function cciph(str) { 
  var code = "";

  switch {switch (str) {
    case 'A':
      code = "N";
      break;
    case 'B:
      code = 'O';
      break;
      //.....
    case 'M':  code = 'Z';
  }
  return str; 
}

cciph("GUR DHVPX OEBJA QBT WHZCRQ BIRE GUR YNML SBK.");

Answer 1

I don't know about a switch, but this will give you all 26 possible mutations of the string, theoretically including the decoded 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"];


function cciph(cipherText) {
  for(i = 0; i < 26; i++) {
    var decodedText = cipherText.split("").map(function(c) {
      var charIndex = alphabet.indexOf(c.toLowerCase());
      if (charIndex == -1) {
        return c;
      }
      var modifiedIndex = charIndex + i;
      var correctedIndex = modifiedIndex % 26;
      return alphabet[correctedIndex];
    });
    console.log(decodedText.join(""));
  }
}

cciph("GUR DHVPX OEBJA QBT WHZCRQ BIRE GUR YNML SBK.");