详解Python判定IP地址合法性的三种方法

import re
def check_ip(ipAddr):
  compile_ip=re.compile('^(1\d{2}|2[0-4]\d|25[0-5]|[1-9]\d|[1-9])\.(1\d{2}|2[0-4]\d|25[0-5]|[1-9]\d|\d)\.(1\d{2}|2[0-4]\d|25[0-5]|[1-9]\d|\d)\.(1\d{2}|2[0-4]\d|25[0-5]|[1-9]\d|\d)$')
  if compile_ip.match(ipAddr):
    return True  
  else:  
    return False

#!/usr/bin/python 
import os,sys 
def check_ip(ipAddr): 
    import sys 
    addr=ipAddr.strip().split('.') #切割IP地址为一个列表 
    #print addr 
    if len(addr) != 4: #切割后列表必须有4个参数 
        print "check ip address failed!"
        sys.exit() 
    for i in range(4): 
        try: 
            addr[i]=int(addr[i]) #每个参数必须为数字，否则校验失败 
        except: 
            print "check ip address failed!"
            sys.exit() 
        if addr[i]<=255 and addr[i]>=0:  #每个参数值必须在0-255之间 
            pass
        else: 
            print "check ip address failed!"
            sys.exit() 
        i+=1
    else: 
        print "check ip address success!"
if len(sys.argv)!=2: #传参加本身长度必须为2 
    print "Example: %s 10.0.0.1 "%sys.argv[0] 
    sys.exit() 
else: 
    check_ip(sys.argv[1]) #满足条件调用校验IP函数

import IPy 
 def is_ip(address): 
  try: 
    IPy.IP(address) 
    return True 
  except Exception as e: 
    return False