Python抓取页面中超链接(URL)的3中方法比较(HTMLParser、pyquery、正则表达式)
HTMLParser版:
#!/usr/bin/python # -*- coding: UTF-8 -*- import HTMLParser
class UrlParser(HTMLParser.HTMLParser): def__init__(self): HTMLParser.HTMLParser.__init__(self) self.urls = [] def handle_starttag(self, tag, attrs): if tag == 'a': for name,value in attrs: if name == 'href': self.urls.append(value) def geturls(self): return self.urls
if__name__ == '__main__': urls = [] url = UrlParser() url.feed('1111111111<a href="http://www.bccn.net">BCCN</a>2222222<a href="http://bbs.bccn.net">BCCN.BBS</a>333333333') urls += url.geturls() print urls
class UrlParser(HTMLParser.HTMLParser): def__init__(self): HTMLParser.HTMLParser.__init__(self) self.urls = [] def handle_starttag(self, tag, attrs): if tag == 'a': for name,value in attrs: if name == 'href': self.urls.append(value) def geturls(self): return self.urls
if__name__ == '__main__': urls = [] url = UrlParser() url.feed('1111111111<a href="http://www.bccn.net">BCCN</a>2222222<a href="http://bbs.bccn.net">BCCN.BBS</a>333333333') urls += url.geturls() print urls
pyquery版:
#!/usr/bin/python # -*- coding: UTF-8 -*- from pyquery import PyQuery as pq
class UrlParser(): def__init__(self): self.urls = [] def feed(self,data): d = pq(data) if d.find('a'): #关于下面一行,我用d('a').attr('href')只能得到第一个URL,暂时只会用map,不知道有没有别的够pythonic的代码 url = d('a').map(lambda i, e: pq(e)('a').attr('href')) for u in url: self.urls.append(u) def geturls(self): return self.urls
if__name__ == '__main__': urls = [] url = UrlParser() url.feed('1111111111<a href="http://www.bccn.net">BCCN</a>2222222<a href="http://bbs.bccn.net">BCCN.BBS</a>333333333') urls += url.geturls() print urls
class UrlParser(): def__init__(self): self.urls = [] def feed(self,data): d = pq(data) if d.find('a'): #关于下面一行,我用d('a').attr('href')只能得到第一个URL,暂时只会用map,不知道有没有别的够pythonic的代码 url = d('a').map(lambda i, e: pq(e)('a').attr('href')) for u in url: self.urls.append(u) def geturls(self): return self.urls
if__name__ == '__main__': urls = [] url = UrlParser() url.feed('1111111111<a href="http://www.bccn.net">BCCN</a>2222222<a href="http://bbs.bccn.net">BCCN.BBS</a>333333333') urls += url.geturls() print urls
正则表达式版:
#!/usr/bin/python # -*- coding: UTF-8 -*- import re
class UrlParser(): def__init__(self): self.urls = [] def feed(self,data): url = re.findall(r'''<a(\s*)(.*?)(\s*)href(\s*)=(\s*)([\"\s]*)([^\"\']+?)([\"\s]+)(.*?)>''',data,re.S|re.I) for u in url: self.urls.append(u[6]) def geturls(self): return self.urls
if__name__ == '__main__': urls = [] url = UrlParser() url.feed('1111111111<a href="http://www.bccn.net">BCCN</a>2222222<a href="http://bbs.bccn.net">BCCN.BBS</a>333333333') urls += url.geturls() print urls
class UrlParser(): def__init__(self): self.urls = [] def feed(self,data): url = re.findall(r'''<a(\s*)(.*?)(\s*)href(\s*)=(\s*)([\"\s]*)([^\"\']+?)([\"\s]+)(.*?)>''',data,re.S|re.I) for u in url: self.urls.append(u[6]) def geturls(self): return self.urls
if__name__ == '__main__': urls = [] url = UrlParser() url.feed('1111111111<a href="http://www.bccn.net">BCCN</a>2222222<a href="http://bbs.bccn.net">BCCN.BBS</a>333333333') urls += url.geturls() print urls
速度比较:正则表达式 > pyquery > HTMLParser
测试的时候遍历大约1000个页面,正则表达式占绝对优势,这3个速度比例大约是 8:2:1
HTMLParser最慢,pyquery速度大约是它的2倍,正则的速度是它的8倍,看来以后如非必要不再考虑HTMLParser了,用起 来也不如pyquery方便,正则速度倒是很快,功能也强大,前两者能提取的内容用正则全部都能实现,而正则能实现的功能前两者就不一定能实现了。只是正 则的可读性不好。以后遇到数据量大的用正则表达式,数据量不大不考虑时间因素但逻辑复杂的的用pyquery,以后维护起来方便Python抓取页面中超链接(URL)的三中方法比较(HTMLParser、pyquery、正则表达式)