一个简单的python网络爬虫程序（下载博客文章）

import urllib  
import time  
url = ['']*50  
con = urllib.urlopen('http://blog.sina.com.cn/s/articlelist_1197161814_0_1.html').read()  
i = 0  
title = con.find(r'<a title')  
href = con.find(r'href=',title)  
html = con.find(r'.html',href)  
while title!=-1 and href!=-1 and html!=-1 and i<50:  
    url[i] = con[href + 6:html+5]  
    print(url[i])  
    title = con.find(r'<a title=',html)  
    href = con.find(r'href=',title)  
    html = con.find(r'.html',href)  
    i=i+1  
else:  
    print('find end!')       
  
  
j=0  
while j<50:  
    content = urllib.urlopen(url[j]).read()  
    print('downloading......'+str(j+1))  
    open(r'likaifu/'+url[j][-26:],'w+').write(content)  
    j=j+1  
    time.sleep(15)  
else:  
    print('download title')