2019-05-14 Python SSL

解决SSL报错问题

-- 导库

import ssl
import urllib.request

context = ssl._create_unverified_context()

--用urllib 代替 requests

--请求

request = urllib.request.Request(url, headers=header)
res = urllib.request.urlopen(request, context=context).read()
soup = BeautifulSoup(res, 'lxml')

--下载

# html = requests.get(href, header_fangzheng).content
request = urllib.request.Request(href, headers=header_fangzheng)
html = urllib.request.urlopen(request, context=context).read()
with open(file, 'wb') as f:
f.write(html)
f.close()

--标签规则变化问题

若报错，就捕捉错误，用

try :

except:
    try:
    except Exception as e：
        print(e)

　　

无报错，那么定位的元素就是空列表

if  a==[]:
    a=soup.select()