你如何用 python 修复 - TypeError: must be str, nor int -？

Question

def rotate(letter, key):
  new = ord(letter)
  new = chr(new) + key
  return new

new = rotate(" "," ")
print(new)

for some reason the code allows me to enter the message and key but then gives me the TypeError.

Answer 1

new is the character code of letter . You should be adding to new before you convert it back to a character, not after.

new = chr(new + key)

Answer 2

If I am formatting your code correctly, I think that your code looks like the following:

def rotate(letter, key):
    new = ord(letter)
    new = chr(new) + key
    return new

The ord function takes a letter and outputs the character code for that letter. The chr function takes a character code and turns it back into a letter. What's happened is that you are adding key to the letter, not to the number and you can't do that. I think that what you were expecting is that rather than having chr(new) + key you would have chr(new + key) . So the code would look as follows:

def rotate(letter, key):
    new = ord(letter)
    new = chr(new + key)
    return new

This can be done shorter as well by combining the chr , ord , and return .

def rotate(letter, key):
    return chr(ord(letter) + key)