1)①爬取中国新闻网科技相关部分新闻

 1 __author__ = ‘minmin‘
 2 #coding:utf-8
 3 import re,urllib,sgmllib,os
 4 
 5 #根据当前的url获取html
 6 def getHtml(url):
 7     page = urllib.urlopen(url)
 8     html = page.read()
 9     page.close()
10     return html
11 
12 #根据html获取想要的文章内容
13 def func(str):
14      result =   re.findall(r"<p.*?>([^<>]*)</p>",getHtml(url),re.M)
15      artical =‘‘
16 
17      for j in result:
18          if len(j)<>0:
19              j = j.replace("<strong>","    ")
20              j = j.replace("</strong>","    ")
21              j = j.replace("<br>","   ")
22              j = j.replace("&nbsp;"," ")
23              j = j.replace("&ldquo;"," ")
24              j = j.replace("&rdquo;"," ")
25              j = j.replace("&middot;"," ")
26              artical = artical + j + ‘\n‘
27      return  artical
28 
29 #html链接的标签是“a”，链接的属性是“href”，也就是要获得html中所有tag=a，attrs=href 值。
30 class URLPaser(sgmllib.SGMLParser):
31     def reset(self):
32         sgmllib.SGMLParser.reset(self)
33         self.urls = []
34 
35     def start_a(self,attrs):
36         href = [v for k,v in attrs if k == ‘href‘]
37         if href:
38             self.urls.extend(href)
39 
40 IParser = URLPaser()
41 socket = urllib.urlopen("http://economy.china.com/internet/")#打开这个网页
42 
43 #fout = file(‘qq_art_urls.txt‘,‘w‘)#要把这个链接写到这个文件中
44 IParser.feed(socket.read())#分析啦
45 
46 reg = ‘http://economy.china.com/internet/.*‘#这个是用来匹配符合条件的链接，使用正则表达式匹配
47 
48 pattern = re.compile(reg)
49 
50 os.getcwd()#获得当前文件夹路径
51 os.path.sep#当前系统路径分隔符
52 
53 #判断文件是否存在
54 if os.path.exists(‘china_news_Technology‘)==False:
55      os.makedirs(‘china_news_Technology‘)
56 i = 0
57 url2 = []
58 for url in IParser.urls:#链接都存在urls里
59     url = "http://economy.china.com"+url
60     if pattern.match(url):
61         if url not in url2:
62             url2.append(url)
63             url = url.replace(".html","_all.html#page_2")#由于一篇文章被分成几页，找到显示全页的那一个页面
64             artical = func(url)
65             if len(artical)<>0:
66                   print artical
67                   print url
68                   i = i + 1
69                   f = open("china_news_Technology/"+str(i) + ‘.txt‘,‘a+‘)
70                   f.write(artical)
71                   f.close()