如何修改Encrypt、Decrypt脚本实现整份文本文件的加密解密

现有代码核心问题 #

• Encrypt.py 仅接收用户直接输入的短文本做加密，未读取输入文件内容、也未将加密结果写入指定输出文件
• Decrypt.py 误将输入的文件名字符串当做加密内容处理，未读取输入文件内容、也未将解密结果写入指定输出文件

修改后的Encrypt.py代码 #

"""
File: encrypt.py
Project 4.3

Encrypts a text file.  The inputs are the names of
the input file and the output file and the distance value.
The encrypted code is witten to a new file.
"""

input_file = input("Enter the input file name: ")
output_file = input("Enter the output file name: ")
distance = int(input("Enter the distance value: "))

# 读取输入文件明文内容
with open(input_file, 'r', encoding='utf-8') as f:
    plainText = f.read()

code = ""
for ch in plainText:
    # 仅处理小写字母，其余字符原样保留
    if ch.islower():
        ordValue = ord(ch)
        cipherValue = ordValue + distance
        if cipherValue > ord('z'):
            cipherValue = ord('a') + distance - \
                          (ord('z') - ordValue + 1)
        code +=  chr(cipherValue)
    else:
        code += ch

# 将加密结果写入输出文件
with open(output_file, 'w', encoding='utf-8') as f:
    f.write(code)

修改后的Decrypt.py代码 #

"""
File: decrypt.py
Project 4.3

Decrypts a file of encrypted text. and prints
the result.  The other input is the distance value.
"""

input_file = input("Enter the input file name: ")
output_file = input("Enter the output file name: ")
distance = int(input("Enter the distance value: "))

# 读取输入文件加密内容
with open(input_file, 'r', encoding='utf-8') as f:
    code = f.read()

plainText = ''
for ch in code:
    # 仅处理小写字母，其余字符原样保留
    if ch.islower():
        ordValue = ord(ch)
        cipherValue = ordValue - distance
        if cipherValue < ord('a'):
            cipherValue = ord('z') - (distance - \
                                      (ordValue - ord('a')) - 1)
        plainText +=  chr(cipherValue)
    else:
        plainText += ch

# 将解密结果写入输出文件
with open(output_file, 'w', encoding='utf-8') as f:
    f.write(plainText)

说明：当前逻辑默认仅处理小写字母，其余字符（大写、空格、标点、数字等）会原样保留，若需要支持其他字符的加解密，可自行调整字符范围判断规则。

内容的提问来源于stack exchange，提问作者chiggywiggy