HTMLParser是python用来解析html的模块。它可以分析出html里面的标签、数据等等，是一种处理html的简便途径。HTMLParser采用的是一种事件驱动的模式，当HTMLParser找到一个特定的标记时，它会去调用一个用户定义的函数，以此来通知程序处理。它主要的用户回调函数的命名都是以handler_开头的，都是HTMLParser的成员函数。当我们使用时，就从HTMLParser派生出新的类，然后重新定义这几个以handler_开头的函数即可。这几个函数包括：
handle_startendtag 处理开始标签和结束标签
handle_starttag 处理开始标签，比如
handle_endtag 处理结束标签，比如
handle_charref 处理特殊字符串，就是以开头的，一般是内码表示的字符
handle_entityref 处理一些特殊字符，以&开头的，比如
handle_data 处理数据，就是
handle_comment 处理注释
handle_decl 处理
handle_pi 处理形如的东西
这里我以从网页中获取到url为例，介绍一下。要想获取到url，肯定是要分析标签，然后取到它的href属性的值。下面是代码：
#-*- encoding: gb2312 -*-
import HTMLParser
class MyParser(HTMLParser.HTMLParser):
def __init__(self):
HTMLParser.HTMLParser.__init__(self)
def handle_starttag(self, tag, attrs):
# 这里重新定义了处理开始标签的函数
if tag == 'a':
# 判断标签<a>的属性
for name,value in attrs:
if name == 'href':
print value
if __name__ == '__main__':
a = '<html><head><title>test</title><body><a href="http://www.163.com">链接到163</a></body></html>'
my = MyParser()
# 传入要分析的数据，是html的。
my.feed(a)
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