這兩天學習了python3實現抓取網頁資源的方法，發現了很多種方法，所以，今天添加一點小筆記。

1、最簡單

import urllib.requestresponse = urllib.request.urlopen('http://python.org/')html = response.read() 

2、使用 Request

import urllib.request req = urllib.request.Request('http://python.org/')response = urllib.request.urlopen(req)the_page = response.read()

3、發送數據

#! /usr/bin/env python3 import urllib.parseimport urllib.request url = 'http://localhost/login.php'user_agent = 'Mozilla/4.0 (compatible; MSIE 5.5; Windows NT)'values = {     'act' : 'login',     'login[email]' : 'yzhang@i9i8.com',     'login[password]' : '123456'     } data = urllib.parse.urlencode(values)req = urllib.request.Request(url, data)req.add_header('Referer', 'http://www.python.org/')response = urllib.request.urlopen(req)the_page = response.read() print(the_page.decode("utf8"))

4、發送數據和header

#! /usr/bin/env python3 import urllib.parseimport urllib.request url = 'http://localhost/login.php'user_agent = 'Mozilla/4.0 (compatible; MSIE 5.5; Windows NT)'values = {     'act' : 'login',     'login[email]' : 'yzhang@i9i8.com',     'login[password]' : '123456'     }headers = { 'User-Agent' : user_agent } data = urllib.parse.urlencode(values)req = urllib.request.Request(url, data, headers)response = urllib.request.urlopen(req)the_page = response.read() print(the_page.decode("utf8"))

5、http 錯誤

#! /usr/bin/env python3 import urllib.request req = urllib.request.Request('http://www.python.org/fish.html')try:  urllib.request.urlopen(req)except urllib.error.HTTPError as e:  print(e.code)  print(e.read().decode("utf8"))

6、異常處理1

#! /usr/bin/env python3 from urllib.request import Request, urlopenfrom urllib.error import URLError, HTTPErrorreq = Request("http://twitter.com/")try:  response = urlopen(req)except HTTPError as e:  print('The server couldn/'t fulfill the request.')  print('Error code: ', e.code)except URLError as e:  print('We failed to reach a server.')  print('Reason: ', e.reason)else:  print("good!")  print(response.read().decode("utf8"))

7、異常處理2

#! /usr/bin/env python3 from urllib.request import Request, urlopenfrom urllib.error import URLErrorreq = Request("http://twitter.com/")try:  response = urlopen(req)except URLError as e:  if hasattr(e, 'reason'):    print('We failed to reach a server.')    print('Reason: ', e.reason)  elif hasattr(e, 'code'):    print('The server couldn/'t fulfill the request.')    print('Error code: ', e.code)else:  print("good!")  print(response.read().decode("utf8"))

8、HTTP 認證

#! /usr/bin/env python3 import urllib.request # create a password managerpassword_mgr = urllib.request.HTTPPasswordMgrWithDefaultRealm() # Add the username and password.# If we knew the realm, we could use it instead of None.top_level_url = "https://cms.tetx.com/"password_mgr.add_password(None, top_level_url, 'yzhang', 'cccddd') handler = urllib.request.HTTPBasicAuthHandler(password_mgr) # create "opener" (OpenerDirector instance)opener = urllib.request.build_opener(handler) # use the opener to fetch a URLa_url = "https://cms.tetx.com/"x = opener.open(a_url)print(x.read()) # Install the opener.# Now all calls to urllib.request.urlopen use our opener.urllib.request.install_opener(opener) a = urllib.request.urlopen(a_url).read().decode('utf8')print(a)