1、有些網站需要登入後才能訪問某個頁面，在登入之前，你想抓取某個頁面內容，登陸前與登陸後是不同的，或者不允許的。
  使用Cookie和使用代理IP一樣，也需要建立一個自己的opener。在HTTP包中，提供了cookiejar模組，用於提供對Cookie的支援。

2 將Cookie儲存到變數中

def getCookeis():
    #declare a cookiejar object instance to save cookie
    cookie=cookiejar.CookieJar();
    #create cookie processor by HTTPCookieProcessor object of urllib.request lib
    handler=request.HTTPCookieProcessor(cookie);
    #create opener
    opener=request.build_opener(handler);
    #open web page
    response=opener.open('http://www.baidu.com')
    for item in cookie:
        print('Name=%s' %item.name)
        print('Value=%s' %item.value)
 

3、儲存Cookie到檔案

def getCookiesToTxt():
    filename = '..\\file\cookie.txt'
    cookie = cookiejar.MozillaCookieJar(filename)
    handler=request.HTTPCookieProcessor(cookie)
    opener = request.build_opener(handler)
    response = opener.open('http://www.baidu.com')
    #ignore_discard:even if the cookie will be discared, it will be preserved
    #ignore_expires:if cookies exits in the file,overwrite the original file
    cookie.save(ignore_discard=True, ignore_expires=True)
 

4、從檔案中獲取Cookie並訪問

def getCookiesFromTxt():
    filename = '..\\file\cookie.txt'
    #create MozillaCookieJar instance object
    cookie = cookiejar.MozillaCookieJar()
    #get cookie from the file to variables
    cookie.load(filename, ignore_discard=True, ignore_expires=True)
    handler=request.HTTPCookieProcessor(cookie)
    opener = request.build_opener(handler)
    response = opener.open('http://www.baidu.com')
    print(response.read().decode('utf-8'))
 

5、利用cookies模擬登入，這裡選擇的是http://www.biqukan.comhttps網站總是不成功，這個網站目前是http的

def simulateLogin():
    #login url
    login_url = 'http://www.biqukan.com/user/login.php?action=login&usecookie=1&url=http://www.biqukan.com/'
    #User-Agent infromation
    user_agent = r'Mozilla/5.0 (Windows NT 6.2; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/27.0.1453.94 Safari/537.36'
    #Headers information
    head = {'User-Agnet': user_agent, 'Connection': 'keep-alive'}
    #login Form_Data information
    Login_Data = {}
    Login_Data['password'] = 'yourpassword'
    Login_Data['username'] = 'yourname'

    #convert to standard format
    logingpostdata = parse.urlencode(Login_Data).encode('utf-8')
    cookie = cookiejar.CookieJar()
    cookie_support = request.HTTPCookieProcessor(cookie)
    opener = request.build_opener(cookie_support)
    req1 = request.Request(url=login_url, data=logingpostdata, headers=head)

    data_url = 'http://www.biqukan.com/user/bookcase.php'
    req2 = request.Request(url=data_url, headers=head)
    try:
        response1 = opener.open(req1)
        response2 = opener.open(req2)
        html = response2.read().decode('gbk')
        print (html)

    except error.URLError as e:
        if hasattr(e, 'code'):
            print("HTTPError:%d" % e.code)
        elif hasattr(e, 'reason'):
            print("URLError:%s" % e.reason)