Javascript:如何有选择地将字符串转换为其各自的Unicode值，加1，然后再转换回字符串？

function convertStringToUnicode(str) {
  let result = "";
  for (let i = 0; i < str.length; i++) {
    let unicode = str.charCodeAt(i);
    unicode += 1;
    result += String.fromCharCode(unicode);
  }
  return result;
}

let originalString = "Hello";
let convertedString = convertStringToUnicode(originalString);
console.log(convertedString); // 输出 "Ifmmp"

function convertUnicodeToString(str) {
  let result = "";
  for (let i = 0; i < str.length; i++) {
    let unicode = str.charCodeAt(i);
    unicode -= 1;
    result += String.fromCharCode(unicode);
  }
  return result;
}

let convertedString = "Ifmmp";
let originalString = convertUnicodeToString(convertedString);
console.log(originalString); // 输出 "Hello"