Question

尝试在python中创建加密/解密程序，从文件中读取消息，使用两个关键字加密，然后输出到另一个文件。此外，它可以反过来做到这一点。我遇到了len（）函数的问题：我得到错误：在函数或方法中构建的类型的对象在此代码段中没有len（）：

    if (len(line)) == 0:
        fileRead = True

在上下文中，这是整个计划：

print("Welcome to Python Encrypt 2015")
print("Only enter alphabet charcters into the file - no punctuation!")

#repeat loop for using program again and so on...
finished = False
while not finished:

#input and validation of encrypt/decrypt input
option = input("Do you want to encrypt or decrypt? (E/D): ")
while "E" != option != "D":
        option = input("Only input 'E' or 'D'! Do you want to encrypt or decrypt? (E/D): ")

#file to be encrypted/decrypted is opened to read
message = ""
fileRead = False
if option == "E":
    file = open("Task3Decrypted.txt","r")
else:
    file = open("Task3Encrypted.txt","r")

#message from 'to encrypt' file is read and outputted to variable
while not fileRead:
    line = (file.readline()).strip()
    if line.isalpha()==True:
        line = line.lower
    else:
        input("Message contains numbers or symbols. Please correct! Press any key to continue: ")
        sys.exit
    if (len(line)) == 0:
        fileRead = True
    else:
        message = message + line
#file closed - saving it
file.close()

#validating keyword and stretching and cutting to length of message
key1True = False
while key1True == False:
    keyword1 = input("Enter your first keyword: ")
    if keyword1.isalpha()==True:
        keyword1 = keyword1.lower()
        key1True = True
key1length = len(keyword1)
while len(keyword1)<len(message):
    keyword1=keyword1+keyword1
keyword1=keyword1[:len(message)]

key2True = False
while key2True == False:
    keyword2 = input("Enter your second keyword: ")
    if keyword2.isalpha()==True:
        keyword2 = keyword2.lower()
        key2True = True
key2length = len(keyword2)
while len(keyword2)<len(message):
    keyword2=keyword2+keyword2
keyword2=keyword2[:len(message)]

newMessage = ""
for i in range(len(message)):
    char = ord(message[i])-96
    key1 = ord(keyword1[i])-96
    key2 = ord(keyword2[i])-96
    if char==-64:
        newMessage = newMessage+" " 
    else:
        if option == "E":
            #clearing original file for security
            clearFileE = open("Task3Decrypted.txt","w")
            clearFileE.close
            #encryption
            if char+key1+key2>26:
                newMessage = newMessage+chr(char+key1+key2-26+96)
            else:
                newMessage = newMessage+chr(char+key1+key2+96)
            newFile = open("Task3Encrypted.txt","w")
            newFile.write(newMessage)
            newFile.close()

        else:
            clearFileD = open("Task3Encrypted.txt","w")
            clearFileD.close
            #decryption
            if char-key1-key2<1:
                newMessage = newMessage+chr(char-key1-key2+26+96)
            else:
                newMessage = newMessage+chr(char-key1-key2+96)
            newFile = open("Task3Decrypted.txt","w")
            newFile.write(newMessage)
            newFile.close()

carryOn = input("Do you want to encrypt/decrypt another message? (Y/N): ") 
while "Y" != carryOn != "N":
    carryOn = input("Only input 'Y' or 'N'! Do you want to encrypt/decrypt another message? (Y/N): ") 
if carryOn == "N":
    finished = True

提前致谢！

Answer 1

你遗漏了

中的括号

line = line.lower()

如果没有（），则设置为lower（）函数本身的对象，因此出现错误消息。

尝试使用两个关键字创建读写文件和加密的加密程序。 len（）函数不起作用

1 个答案: