How to get the next consecutive ASCII character?

Seems I have forgotten C almost totally. How do you do the following: Let's suppose we have a line: inputString += (inChar); Now, if for ex. inChar is "A" =65, how do I make the inputString to contain the next alphabet ="B" anstead of "A" with string/char operations? Maybe I need to convert "A" to int and add 1 to it, then convert it pack to char or how? thx

Is inputString a String variable? If so I can't help you.

If inputString is a char variable then it's easy. Just add 1.

char ch = 'A';
ch += 1;
Serial.print(ch);

Will print

B

You can also use String if you wish, although using the String class is probably not the best choice. Is this what you’re trying to do?

void setup() {  
  int index;
  char myChar;
  String inputString = "ABCD";
  String newStr;
  Serial.begin(115200);
  
  newStr = inputString;
  for (index = 0; index < inputString.length(); index++) {
    myChar = (char) newStr[index];
    newStr[index] = myChar + 1;
  }
  Serial.println(newStr);
  
}

void loop() {
}

Thank you Delta_G & econjack. I knew it is simple, lol