How to check password validity with Python

In this program we take the password as a combination of alphanumeric characters and special characters and check whether the password is valid or not with the help of several conditions.

Main conditions for password verification:

1. At least 8 characters.

2. The letters must be between [az]

3. At least one letter should be uppercase [AZ]

4. At least between [0-9] There is 1 number or number.

5. At least 1 character from [_ or @ or $].

Example:

import re 
password = "R@m@_f0rtu9e$"
flag = 0
while True:   
    if (len(password)<8): 
        flag = -1
        break
    elif not re.search("[a-z]", password): 
        flag = -1
        break
    elif not re.search("[A-Z]", password): 
        flag = -1
        break
    elif not re.search("[0-9]", password): 
        flag = -1
        break
    elif not re.search("[_@$]", password): 
        flag = -1
        break
    elif re.search("\s", password): 
        flag = -1
        break
    else: 
        flag = 0
        print("有效密码") 
        break
  
if flag ==-1: 
    print("无效密码")

Output:

有效密码

Here we use the re module, which provides support for regular expressions in Python. In addition to this, the re.search() method returns False if the first parameter is not found in the second parameter. This method is best suited for testing regular expressions rather than extracting data. We use re.search() to check the validation of letters, numbers or special characters. To check for spaces we use "\s" from the regular expression module.

Recommended course: "Python Tutorial"

This article is about the method of checking the validity of passwords in Python programs. I hope it will be helpful to friends in need!

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