python - 凯撒密码按关键字的 ASCII 值而不是数字进行移位

Question

我被分配用 python 编写凯撒密码程序。我使用数字来移动/加密消息，但现在我需要使用关键字。关键字重复足够多的次数以匹配明文消息的长度。将关键短语的每个字母的字母值与明文消息的每个字母的字母值相加以生成加密文本。

MAX_KEY_SIZE = 26
def getMode():
    while True:
        print('Do you wish to encrypt or decrypt a message?')
        mode = input().lower()
        if mode in 'encrypt e decrypt d'.split():
            return mode
        else:
            print('Enter either "encrypt" or "e" or "decrypt" or "d".')
def getMessage():
    print('Enter your message:')
    return input()
def getKey():
    key = 0
    while True:
        print('Enter the key number (1-%s)' % (MAX_KEY_SIZE))
        key = int(input())
        if (key >= 1 and key <= MAX_KEY_SIZE):
            return key
def getTranslatedMessage(mode, message, key):
    if mode[0] == 'd':
        key = -key
    translated = ''
    for symbol in message:
        if symbol.isalpha():
            num = ord(symbol)
            num += key
            if symbol.isupper():
                if num > ord('Z'):
                    num -= 26
                elif num < ord('A'):
                    num += 26
            elif symbol.islower():
                if num > ord('z'):
                    num -= 26
                elif num < ord('a'):
                    num += 26
            translated += chr(num)
        else:
            translated += symbol
    return translated
mode = getMode()
message = getMessage()
key = getKey()
print('Your translated text is:')
print(getTranslatedMessage(mode, message, key))
getMode()
getMessage()
getKey()
getTranslatedMessage(mode, message, key)
getTranslatedMessage(mode, message, key)

Answer 1

要获取单词中所有字符的 ASCII 值相加(将单词转换为数字)，此函数应该有效:

def word_to_num(word):
    word = str(word) #Check it is a string
    ascii_value = 0
    for i in word:
        ascii_value += ord(i) #You can use many operations here
    return ascii_value

在代码开头定义它，然后传入关键字将其转换为数字值。然后您可以使用您拥有的数字密码代码。