Caesars Cipher, array not storing new values

Tell us what’s happening:
Hi there, i am trying to convert str to an Array with the ASCII code but I dont know what I am doing wrong and my newArray is not storing the values…

Your code so far

function rot13(str) { // LBH QVQ VG!
 var newArray = [];
  var corto= str.split("");

   for (var i=0; i<corto.lentgh; i++){
   
  newArray.push(corto.charCodeAt([i])); 
  
  }

  return newArray;
}

// Change the inputs below to test
rot13("SERR PBQR PNZC");

Your browser information:

Your Browser User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/64.0.3282.186 Safari/537.36.

Link to the challenge:
https://www.freecodecamp.org/challenges/caesars-cipher

Issued solved.
function rot13(str) { // LBH QVQ VG!
var newArray = [];
var corto= str.split("");

for (var i=0; i<corto.length; i++){

var nueva= str.charCodeAt(i);
newArray.push(nueva);
}

return newArray;
}