Web开发

python cgi教程5——Cookie

设置Cookie

有两个与cookie相关的操作，设置cookie和读取cookie。


以下例子展示了cookie的设置。

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#!/usr/bin/env python
import time

# This is the message that contains the cookie
# and will be sent in the HTTP header to the client
print 'Set-Cookie: lastvisit=' + str(time.time());

# To save one line of code
# we replaced the print command with a '\n'
print 'Content-Type: text/html\n'
# End of HTTP header

print '<html><body>'
print 'Server time is', time.asctime(time.localtime())
print '</body></html>'

这是在数据头中使用Set-Cookie进行的操作。


检索Cookie


浏览器返回来的cookie存放于os.environ字典中，对应的字段名为’HTTP_COOKIE’。以下是一个例子：

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#!/usr/bin/env python
import Cookie, os, time

cookie = Cookie.SimpleCookie()
cookie['lastvisit'] = str(time.time())

print cookie
print 'Content-Type: text/html\n'

print '<html><body>'
print '<p>Server time is', time.asctime(time.localtime()), '</p>'

# The returned cookie is available in the os.environ dictionary
cookie_string = os.environ.get('HTTP_COOKIE')

# The first time the page is run there will be no cookies
if not cookie_string:
   print '<p>First visit or cookies disabled</p>'

else: # Run the page twice to retrieve the cookie
   print '<p>The returned cookie string was "' + cookie_string + '"</p>'

   # load() parses the cookie string
   cookie.load(cookie_string)
   # Use the value attribute of the cookie to get it
   lastvisit = float(cookie['lastvisit'].value)
   
   print '<p>Your last visit was at',
   print time.asctime(time.localtime(lastvisit)), '</p>'

print '</body></html>'

使用SimpleCookie对象的load()方法对字符串进行解析。