urllib:处理网络异常

from urllib import request, error
import ssl
import urllib.request
import socket
import urllib.error
ssl._create_default_https_context = ssl._create_unverified_context

1.URLError

try:
    response = request.urlopen('http://gxj.com')
except error.URLError as e:
    print(e.reason)

2.HTTPError

try:
    response =request.urlopen('https://cuiqingcai.com/index.htm')
except error.HTTPError as  e:
    print(e.code, e.headers, e.reason)

3.最好的写法先捕获子类的错误在捕获父类

try:
    response = request.urlopen('https://cuiqingcai.com/index.htm')
except error.HTTPError as e:
    print(e.reason, e.code, e.headers)
except error.URLError as e:
    print(e.reason)
else:
    print('Request Successfully')
#4.error 里reason属性返回的不一定是字符串，也可能是一个对象
try:
    response = urllib.request.urlopen('https://cuiqingcai.com', timeout=1)
except socket.timeout as e:
    print(type(e))