介绍python的Xpath的python开元项目:

1.libxml2-python-2.6.4.tar.gz

 

安装：下载对应python版本的软件包à解压àpython setup.py install

  

例一：
     
import libxml2
     
def text() :
    
doc = libxml2.parseFile('/tmp/books.xml')
    
for book in doc.xpathEval('/bookstore/book') :
    
        print book.content
     
doc.freeDoc()
    

     
       
     
例二
    
import libxml2
     
doc = libxml2.parseFile('/tmp/books.xml')
     
doc.xpathEval('/bookstore/book[1]/price + /bookstore/book[1]/price ')
     
doc.xpathEval('/bookstore/book[2]/price < 0')
     
doc.freeDoc()
    

    
      
    
例三
    
import libxml2
     
doc = libxml2.parseFile('/tmp/books.xml')
    
doc.xpathEval('child::book') #返回的结果是什么？为什么
     
doc.xpathEval('child::bookstore')
     
doc.xpathEval('descendant::bookstore')
     
doc.freeDoc()
    

     
       
     
例四： 
      
import libxml2
     
doc = libxml2.parseFile('/tmp/books.xml')
     
doc.xpathEval('/bookstore/book[price>35.00]')[0].content
     
doc.xpathEval('/bookstore/book[last()]')
     
doc.freeDoc()

 

2.Google的开源项目，python官方网站上推荐的xpath项目，版本为0.1

 

http://py-dom-xpath.googlecode.com/files/py-dom-xpath-0.1.tar.gz

 

安装：下载软件包à解压àpython setup.py install

  

例一
     
import xpath
     
import xml.dom.minidom
     
xml = xml.dom.minidom.parse('/tmp/books.xml')
     
doc = xml.documentElement
     
xpath.find('/bookstore/book[1]', doc)[0].toxml()
     
xpath.find('/bookstore', doc)
     

     
       
     
例二
     
import xpath
     
import xml.dom.minidom
     
xml = xml.dom.minidom.parse('/tmp/books.xml')
     
doc = xml.documentElement
     
context = xpath.XPathContext()
     
context.variables['max'] = 100
     
context.variables['min'] = 4
     
context.findvalues('//book[price>=$min and price<=$max]', doc)
     

     
       
     
还可以根据命名空间查询
     
详细参考文档：http://py-dom-xpath.googlecode.com/svn/trunk/doc/index.html
     

     
       

 

3.用python中自带的库解析xml

  

from xml.etree import ElementTree as XmlTree
     
xmlDoc = XmlTree.parse('/tmp/books.xml')
     
xmlRoot = xmlDoc.getroot()
     
value = xmlRoot.find('book/price').text
     
print value