Question

我正在使用Python中的正则表达式解决运动问题，并使用Python自动化无聊的东西。问题和我的代码如下。我在Python shell中使用正则表达式，我认为它是正确的，但我不能让它在我的函数中工作，以便它返回正确的答案。

编写一个使用正则表达式的函数，以确保传递的密码字符串很强。强密码定义为长度至少为八个字符，包含大写和小写字符，并且至少有一个数字的密码。您可能需要针对多个正则表达式模式测试字符串以验证其强度。

import re

def pwRegex():



print "Please enter a password"

user_pw = raw_input("> ")

#your_pw = str(user_pw)

passGex = re.compile(r'^(?=.*\d)(?=.*[A-Z])\w{8,15}$')

pass_w = passGex.search(user_pw)
if pass_w != '':

    print "Well done"
else:
    print "Try again"


pwRegex()

我得到的输出是＆＃34;再试一次＆＃34;每次即使我输入的密码都应该通过正则表达式。我尝试制作if语句pass_w == True:但是我输入的所有内容似乎都通过了正则表达式，即使它不正确。

Answer 1

在python中进行正则表达式搜索会返回MatchObject，而不是字符串。如果找不到所需的模式，它将返回None。你应该检查None，或者更热情地检查真实性

# if pass_w != None: # => less pythonic
if pass_w:
    print 'Well done'
else:
    print 'Try again'

Answer 2

import re
print('Please set a new password: ')

def strongpassword():
    while True:
        password = input()        
        if lowcase.search(password) == None:
            print('The entered password doesn\'t have a lower case character')
            continue        
        if upcase.search(password) == None:
            print('The entered password doesn\'t have an upper case character')
            continue        
        if digit.search(password) == None:
            print('The entered password doesn\'t have a digit')
            continue        
        if space_8.search(password) == None:
            print('The entered password should have atleast 8 characters and no space in between')
            continue
        else:
            print('New Password is Valid and Saved')
            break


lowcase = re.compile(r'[a-z]')              # this regex searches for atleast one lower case alphabet
upcase = re.compile(r'[A-Z]')               # this regex searches for atleast one upper case alphabet
digit = re.compile(r'(\d)')                 # this regex searches for atleast one digit
space_8 = re.compile(r'^[a-zA-Z0-9]{8,}$')  # this regex searches for expressions without any space and atleast 8 characters 

strongpassword()

Answer 3

我猜，它已经不相关了。不过，我想建议一下：

  import re

  pasword = re.compile(r'''(
  \d+ #have at lest one digit
  .* # anything
  [A-Z]+ # at least 1 capital
  .*
  [a-z]+ # at least one lower
  .* 
  )''', re.VERBOSE)

  # test
  pasword.search('1@#A!a').group()

 def is_strong_password():
 pas = input('Enter a password:')
 if len(pas) < 8:
    return False
 else:
    check = pasword.search(''.join(sorted(pas))).group() #sorted is important to be sure that user can write symbols in any order he/she wants
  if (not check):
      print('Not strong pasword')
      return False
  else:
      print('Strong password')
      return True

Answer 4

我也在做同样的练习，我也在学习 Python。您可以使用 search() 代替 findall()。我只是用它来测试一下。

import re
print('Enter new password')
def strongPW():
while True:
    pw = input()

    lowercase = []  # lowercase
    uppercase = []  # uppercase
    digit = []  # number

    if len(pw) < 8:
        print('your password must have 8 characters or more')
        break

# lowercase verification

    pwRegex = re.compile(r'[a-z]')
    lowercase = pwRegex.search(pw)
    if lowercase == []:
        print('Your password must have at least one lowercase')
        break

# uppercase verification

    uppercaseRegex = re.compile(r'[A-Z]')
    uppercase = uppercaseRegex.findall(pw)
    if uppercase == []:
        print('Your password must have at least one uppercase')
        break

# digit verification
    DigitRegex = re.compile(r'[0-9]')
    digit = DigitRegex.findall(pw)
    if digit == []:
        print('Your password must have at least one digit')
        break

    else:
        print('Your password meets all requirements ')
        break


strongPW()

正则表达式密码程序

4 个答案: