如何逐行读取python中的txt文件并将每行设置为一个变量

Question

I have dictionary code which is programmed in python and a word list, the python code which decrypts a specific encrypted text is here:

from Crypto.Cipher import AES
import base64
import os

BLOCK_SIZE = 32

PADDING = '{'

# Encrypted text to decrypt
encrypted = "t0ed+TDTf4e1V3Vz94nAN+nj1uDgMPZnfd7BDyBoy/GeGk6LiImMBPPHvN8DcLgIhWo4ByqxpZby99nQpU8KuA=="

DecodeAES = lambda c, e: c.decrypt(base64.b64decode(e)).rstrip(PADDING)

f = open('words.txt')

for line in f.readlines():
    secret = line.rstrip('\n')
f.close()

if (secret[-1:] == "\n"):
    print "Error, new line character at the end of the string. This will not match!"
elif (len(secret) >= 32):
    print "Error, string too long. Must be less than 32 characters."
else:
    # create a cipher object using the secret
    cipher = AES.new(secret + (BLOCK_SIZE - len(secret) % BLOCK_SIZE) * PADDING)

    # decode the encoded string
    decoded = DecodeAES(cipher, encrypted)

    if (decoded.startswith('FLAG:')):
        print "\n"
        print "Success: "+secret+"\n"
        print decoded+"\n"
    else:
        print 'Wrong password'

I want the code to loop through all lines in the words.txt and try them to check if they are the right value for the decryption process, this code stops when it reads the first line and it output wrong password

Answer 1

If you use rstrip() it removes all the whitespaces along with the new line( \\n ). So use rstrip('\\n') to remove the newlines only. As you want to loop it put the logic inside a for loop.

f = open('words.txt')

for line in f.readlines():
    secret = line.rstrip('\n')
    if (secret[-1:] == "\n"):
        print "Error, new line character at the end of the string. This will not match!"
    elif (len(secret) >= 32):
        print "Error, string too long. Must be less than 32 characters."
    else:
    # create a cipher object using the secret
        cipher = AES.new(secret + (BLOCK_SIZE - len(secret) % BLOCK_SIZE) * PADDING)

    # decode the encoded string
        decoded = DecodeAES(cipher, encrypted)

        if (decoded.startswith('FLAG:')):
            print "\n"
            print "Success: "+secret+"\n"
            print decoded+"\n"
            break
        else:
            print 'Wrong password'
f.close()

Answer 2

Reading line by line happens simply like this

with open('words.txt', 'r') as f:
    for line in f:
        secret = line #Normally there are no \n at the end

        #Use this is in case you still get the \n
        #secret = line.rstrip('\n') 

Answer 3

尝试用空字符串替换换行符：

line = f.readline().replace('\n','')

Answer 4

f = open('<filepath>', 'r')
for line in f.readlines():
    secret = line
    # do something with the line
f.close()

Does this solve your problem?

Answer 5

Each line in a file will contain the newline escape character: \\n at the end of the line.
Here's how you can loop over the file:

f = open('words.txt')

for line in f:
    secret = line[:-1] # will extract a substring not containing the newline char

    # then do what you want with secret like:
    do_decoding(secret)

Hope it helps.