使用正则表达式判断IP是否合法
有socket等库的方法已经实现了IP合法性的检查，这个是某外企(flexport)的面试题，要求不能使用现成的库。
输入：比如1.2.3.4
输出： True or False
- 执行演示
$ python check_ip.py
check_ip('1.2.3.4') : True
check_ip('1.2.3.444') : False
- 参考代码
https://github.com/china-testing/python-testing-examples/tree/master/interview
check_ip.py
#!/usr/bin/env python
# -*- coding: utf-8 -*-
# 技术支持：dwz.cn/qkEfX1u0 项目实战讨论QQ群630011153 144081101
# CreateDate: 2019-12-29
import re
def check_ip(address):
if type(address) != str:
return False
expression = re.compile('\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}')
if not expression.match(address):
return False
for number in address.split('.'):
if number.startswith('0') and len(number) >1 :
return False
if int(number) < 0 or int(number) > 255:
return False
return True
if __name__ == '__main__':
print("check_ip('1.2.3.4')", ": ", check_ip('1.2.3.4'))
print("check_ip('1.2.3.444')", ": ", check_ip('1.2.3.444'))
参考资料
寻找字符串中可能的ip地址
输入：字符串，比如"134578'
输出： IP地址列表
- 执行演示
$ python check_ip2.py
123425 可能的ip有 ['1.234.2.25', '12.34.2.25', '123.4.2.25']
- 参考代码
https://github.com/china-testing/python-testing-examples/tree/master/interview
check_ip2.py
#!/usr/bin/env python
# -*- coding: utf-8 -*-
# 技术支持：dwz.cn/qkEfX1u0 项目实战讨论QQ群630011153 144081101
# CreateDate: 2019-12-29
from check_ip import check_ip as check
def address(s, state=()):
result = []
length = len(s)
start = 1 if not state else state[-1]
for pos in range(start,length):
if pos not in state:
if len(state) == 2:
seqs = state + (pos,)
ip_str = f'{s[:seqs[0]]}.{s[seqs[0]:seqs[1]]}.{s[seqs[1]:seqs[2]]}.{s[seqs[1]:]}'
if check(ip_str):
result.append(ip_str)
else:
result = result + address(s, state + (pos,))
return result
if __name__ == '__main__':
tmp = '123425'
print(tmp, "可能的ip有", address(tmp))
业界常用判断ip方法1
https://github.com/china-testing/python-testing-examples/tree/master/interview
check_ip3.py
image.png
业界常用判断ip方法
https://github.com/china-testing/python-testing-examples/tree/master/interview
check_ip3.py
image.png
check_ip4.py
第三方库IPy也可以达到类似的效果。
