用python来解析xml文件(简单情况)

首先，sax解析最直观，当然，也可以容许xml文件出些错。

先给定一个xml文件book.xml,

<catalog>
<book isbn="0-596-00128-2">
<title>Python & XML</title>
<author>Jones, Drake</author>
</book>
<book isbn="0-596-00085-5">
<title>Programming Python</title>
<author>Lutz</author>
</book>
<book isbn="0-596-00281-5">
<title>Learning Python</title>
<author>Lutz, Ascher</author>
</book>
<book isbn="0-596-00797-3">
<title>Python Cookbook</title>
<author>Martelli, Ravenscroft, Ascher</author>
</book>
<!-- imagine more entries here -->
</catalog>写一个BookHandler, 如下：

# -*- coding: utf-8 -*-

import xml.sax.handler

class BookHandler(xml.sax.handler.ContentHandler):
def __init__(self):
self.inTitle = 0 # handle XML parser events
self.mapping = {} # a state machine model

def startElement(self, name, attributes):
if name == "book": # on start book tag
self.buffer = "" # save ISBN for dict key
self.isbn = attributes["isbn"]
elif name == "title": # on start title tag
self.inTitle = 1 # save title text to follow

def characters(self, data):
if self.inTitle: # on text within tag
self.buffer += data # save text if in title

def endElement(self, name):
if name == "title":
self.inTitle = 0 # on end title tag
self.mapping[self.isbn] = self.buffer # store title text in dict

import xml.sax
import pprint

parser = xml.sax.make_parser( )
handler = BookHandler( )
parser.setContentHandler(handler)
parser.parse('book.xml')

pprint.pprint(handler.mapping)

结果如下：

Process started >>>
{u'0-596-00085-5': u'Programming Python',
u'0-596-00128-2': u'Python & XML',
u'0-596-00281-5': u'Learning Python',
u'0-596-00797-3': u'Python Cookbook'}<<< Process finished.
================ READY ================

不过，这是比较简单的情况了。而且我们可以看到，结果全是以unicode串输出的。