python 判断ip是否正确 re学习

官网链接  https://docs.python.org/zh-cn/3/library/re.html

re 判断ip是否正确

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

　　

re 判断用户输入的域名是否正确

def is_valid_domain(domain):
    pattern = re.compile(
        r'^(([a-zA-Z]{1})|([a-zA-Z]{1}[a-zA-Z]{1})|'
        r'([a-zA-Z]{1}[0-9]{1})|([0-9]{1}[a-zA-Z]{1})|'
        r'([a-zA-Z0-9][-_.a-zA-Z0-9]{0,61}[a-zA-Z0-9])).'
        r'([a-zA-Z]{2,13}|[a-zA-Z0-9-]{2,30}.[a-zA-Z]{2,3})$'
    )
    return True if pattern.match(domain) else False

　　

re判断用户输入的url是否正确

regex = re.compile(
        r'^(?:http|ftp)s?://' # http:// or https://
        r'(?:(?:[A-Z0-9](?:[A-Z0-9-]{0,61}[A-Z0-9])?.)+(?:[A-Z]{2,6}.?|[A-Z0-9-]{2,}.?)|' #domain...
        r'localhost|' #localhost...
        r'd{1,3}.d{1,3}.d{1,3}.d{1,3})' # ...or ip
        r'(?::d+)?' # optional port
        r'(?:/?|[/?]S+)$', re.IGNORECASE)
if re.match(regex, domain) is not None:
        return True

　re 取出用户输入url的域名或者ip

def get_domain(doamin):
    domain_new = re.findall('[^/">]{3,50}.com|[^/">]{4,50}.cn|[^/"><]{3,50}.net.cn', doamin)
    # domain_new=re.findall('[^/"><.]{3,20}.com|[^/"><.]{4,}.cn|[^/"><.]{3,20}.net.cn', doamin)
    try:
        # print(domain_new,'new',doamin)
        if not domain_new:
            reg = re.compile(r'(d{1,3}.d{1,3}.d{1,3}.d{1,3})')
            item = re.findall(reg, doamin)
            if not item:
                return False
            return item[0]
        return domain_new[0]
    except Exception:
        return False