isalpha() 和多个 while 循环的逻辑错误

Question

我正在尝试检查用户是否在输入中输入了一个字母字符，如果没有，它会打印一个字符串。 整个程序供用户选择是否需要密码中的字母、数字或特殊字符。

这是我的代码，但是一旦我进入 special_characters while 循环，就会出现逻辑错误。 当我在 else 语句中输入 yi 时，得到 print("Invalied input, Try again: not y or n") 但如果我输入 n 或其他任何内容，我会得到代码的作用！ 我很困扰：

 import string

 alphabets = list(string.ascii_letters)
 digits = list(string.digits)
 special_characters = list("!@#$%^&*()")
 PasswordCharacters = []

a = True
while a:
  x = True
  y = True
  z = True
  while x:
     alphabets_2 = input("Would you like to include letters in your password?: ")

    if alphabets_2.isalpha():
        if alphabets_2 == "y":
            PasswordCharacters.append(alphabets)
            x = False
        elif alphabets_2 == 'n':
            x = False
        else:
            print("Invail Input, Try Again! not y or n")
    if not alphabets_2.isalpha():
        print("Invaild input! Try again, not a letter")
        continue

  while y:
    digits_2 = input("Would you like to include digits in your password?: ")

    if digits_2.isalpha():
        if digits_2 == 'y':
            PasswordCharacters.append(digits)
            y = False
        elif digits_2 == 'n':
            y = False
        else:
            print("Invaild Input, Try Again! not y or n")
    if not digits_2.isalpha():
        print("Invaild input! Try Again! not a letter")
        continue

  while z:
    special_characters_2 = input("would you like to include special characters in your password?: ")

    if special_characters_2.isalpha():
        if special_characters == 'y':
            PasswordCharacters.append(special_characters)
            z = False
        elif special_characters_2 == 'n':
            z = False
        else:
            print("Invaild input, Try again! not y or n")
    if not special_characters_2.isalpha():
        print("Invaild input, Try again! not a letter")
        continue
a = False
    

我得到一个逻辑错误，当我输入 yi 得到 else 块的打印语句

Answer 1

你有一个错字：

    if special_characters_2.isalpha():
        if special_characters == 'y':  # should be special_characters_2

当您有大量复制和粘贴的代码时，很容易出现这样的拼写错误。 考虑将这个问答循环放在 function 中：

def ask_y_or_n(question):
    while True:
        answer = input(question)
        if answer == "y":
            return True
        if answer == "n":
            return False
        if answer.isalpha():
            print("Invaild Input, Try Again! not y or n")
        else:
            print("Invaild input! Try Again! not a letter")

然后，您可以将代码的整个 x/y/z 部分替换为：

for desc, characters in [
    ("letters", alphabets),
    ("digits", digits),
    ("special characters", special_characters),
]:
    if ask_y_or_n(f"Would you like to include {desc} in your password?: "):
        PasswordCharacters.append(characters)

Answer 2

一个错字：

if special_characters == 'y':

应该是special_characters2 。

而且您实际上不需要将 string.ascii_letters 等转换为列表，因为它基本上是.. 一个列表