在采集网页信息的时候，经常需要伪造报头来实现采集脚本的有效执行

下面，我们将使用urllib2的header部分伪造报头来实现采集信息

方法1、

#!/usr/bin/python
# -*- coding: utf-8 -*-
#encoding=utf-8
#Filename:urllib2-header.py
 
import urllib2
import sys
 
#抓取网页内容-发送报头-1
url= \"http://www.jb51.net\"
send_headers = {
 \'Host\':\'www.jb51.net\',
 \'User-Agent\':\'Mozilla/5.0 (Windows NT 6.2; rv:16.0) Gecko/20100101 Firefox/16.0\',
 \'Accept\':\'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8\',
 \'Connection\':\'keep-alive\'
}
 
req = urllib2.Request(url,headers=send_headers)
r = urllib2.urlopen(req)
 
html = r.read()        #返回网页内容
receive_header = r.info()     #返回的报头信息
 
# sys.getfilesystemencoding() 
html = html.decode(\'utf-8\',\'replace\').encode(sys.getfilesystemencoding()) #转码:避免输出出现乱码 
 
print receive_header
# print \'####################################\'
print html

方法2、

#!/usr/bin/python
# -*- coding: utf-8 -*-
#encoding=utf-8
#Filename:urllib2-header.py
 
import urllib2
import sys
 
url = \'http://www.jb51.net\'
 
req = urllib2.Request(url)
req.add_header(\'Referer\',\'http://www.jb51.net/\')
req.add_header(\'User-Agent\',\'Mozilla/5.0 (Windows NT 6.2; rv:16.0) Gecko/20100101 Firefox/16.0\')
r = urllib2.urlopen(req)
 
html = r.read()
receive_header = r.info()
 
html = html.decode(\'utf-8\').encode(sys.getfilesystemencoding())
 
print receive_header
print \'#####################################\'
print html