python 解析XML expat方式

python 解析XML expat方式

将xml转换成python对象树

今天项目组一个同事要写这样的代码，他之前都是写Java 没用过python，我回来翻了下pythonCookBook这个书

449页有讲

贴代码

#  -*-  codeing:utf-8  -*- 
'''
Created on 2011-12-7

@author: simon
'''

from xml.parsers import expat

class Element(object):
    ''' element '''
    def __init__(self, name, attributes):
        self.name = name
        self.attributes = attributes
        self.cdata = ''
        self.children = [ ]
    def addChild(self,element):
        self.children.append(element)
    def getAttribut(self, key):
        return self.attributes.get(key)
    def getData(self):
        return self.cdata
    def getElements(self, name=''):
        if name:
            return [c for c in self.children if c.name == name]
        else:
            return list(self.children)

class xml2obj(object):
    def __init__(self):
        self.root = None
        self.nodeStack = []
    def StartElement(self, name , attributes):
        'expat start element enent handler'
        element = Element(name.encode( ), attributes)
        if self.nodeStack:
            parent = self.nodeStack[-1]
            parent.addChild(element)
        else:
            self.root = element;
        self.nodeStack.append(element)
    def EndElement(self, name):
        self.nodeStack.pop()
    def CharacterData(self, data):
        if data.strip():
            data = data.encode()
            element = self.nodeStack[-1]
            element.cdata += data
    def Parse(self, filename):
        Parser = expat.ParserCreate()
        Parser.StartElementHandler = self.StartElement
        Parser.EndElementHandler = self.EndElement
        Parser.CharacterDataHandler = self.CharacterData
        ParserStatus = Parser.Parse(open(filename).read(), -1)
        return self.root

parser = xml2obj()
rootElement = parser.Parse("sample.xml")
print rootElement

但是pythonCookBook书上有个错误  上面的代码已经修正

http://oreilly.com/catalog/errataunconfirmed.csp?isbn=9780596007973

有说明

BOOK: Python Cookbook by Alex Martelli; Anna Martelli Ravenscroft; David
Ascher
PUBLISHER: O'Reilly Media, Inc.
DATE OF PUBLICATION: March 18, 2005
Chapter 12. Processing XML
Section: Converting an XML Document into a tree of Python Objects
12.6.2 Solution

[Code... snippet]
def EndElement(self, name):
'Expat end element event handler'
self.nodeStack[-1].pop( )

The code above attempts execute the method pop on an Element object
contained in the nodeStack(list). However, there is no method pop defined
in the Element Class. I believe that it was the authors intention to write.

[Code... snippet]
def EndElement(self, name):
'Expat end element event handler'
self.nodeStack.pop( )

Which pops an element of the stack.