python创建和解析xml文件

python中的xml.dom模块使用的就是传统的dom解析api和方法。所以也就不写什么了，主要就是练习敲敲代码，继续熟悉python。本文通过xml.dom.minidom创建一个xml文档，然后再解析出来，用以熟悉相关接口方法的使用。

创建一个xml文档：

?

'''

Created on 2012-1-10

Create a xml document

@author: xiaojay

'''

from xml.dom import minidom

doc =minidom.Document()

doc.appendChild(doc.createComment("This is a simple xml."))

booklist = doc.createElement("booklist")

doc.appendChild(booklist)

def addBook(newbook):

    book= doc.createElement("book")

    book.setAttribute("id", newbook["id"])

   

    title= doc.createElement("title")

    title.appendChild(doc.createTextNode(newbook["title"]))

    book.appendChild(title)

   

    author= doc.createElement("author")

    name= doc.createElement("name")

    firstname= doc.createElement("firstname")

    firstname.appendChild(doc.createTextNode(newbook["firstname"]))

    lastname= doc.createElement("lastname")

    lastname.appendChild(doc.createTextNode(newbook["lastname"]))

    name.appendChild(firstname)

    name.appendChild(lastname)

    author.appendChild(name)

    book.appendChild(author)

   

    pubdate= doc.createElement("pubdate")

    pubdate.appendChild(doc.createTextNode(newbook["pubdate"]))

    book.appendChild(pubdate)

   

    booklist.appendChild(book)

addBook({"id":"1001","title":"An apple","firstname":"Peter","lastname":"Zhang","pubdate":"2012-1-12"})

addBook({"id":"1002","title":"Love","firstname":"Mike","lastname":"Li","pubdate":"2012-1-10"})

addBook({"id":"1003","title":"Steve.Jobs","firstname":"Tom","lastname":"Wang","pubdate":"2012-1-19"})

addBook({"id":"1004","title":"Harry Potter","firstname":"Peter","lastname":"Chen","pubdate":"2012-11-11"})

f =file("book.xml","w")

doc.writexml(f)

f.close()

　　通过doc.toprettyxml(indent, newl, encoding)方法可以优雅显示xml文档，但是要避免直接写入文本，否则会给解析带来麻烦，尽量使用自带的writexml方法。

生成的文档内容：

<?xml version="1.0" ?>
<!--This is a simple xml.-->
<booklist>
　　<book id="1001">
　　　　<title>
　　　　An apple
　　　　</title>
　　<author>
　　　　<name>
　　　　　　<firstname>
　　　　　　Peter
　　　　　　</firstname>
　　　　　　<lastname>
　　　　　　Zhang
　　　　　　</lastname>
　　　　</name>
　　</author>
　　<pubdate>
　　2012-1-12
　　</pubdate>
　　</book>

.................
</booklist>

解析该xml文档：

?

'''

Created on 2012-1-10

Scan a xml doc

@author: xiaojay

'''

from xml.dom import minidom , Node

class bookscanner:

    def__init__(self,doc):

        for child indoc.childNodes :

            if child.nodeType == Node.ELEMENT_NODE \

            and child.tagName == "book" :

               bookid =child.getAttribute("id")

               print "*"*20

               print "Book id : ", bookid

               self.handle_book(child)

               

    defhandle_book(self,node):

        for child innode.childNodes :

            if child.nodeType == Node.ELEMENT_NODE :

               if child.tagName=="title":

                   print "Title : ", self.getText(child.firstChild)

               if child.tagName=="author":

                   self.handle_author(child)

               if child.tagName=="pubdate":

                   print "Pubdate : ", self.getText(child.firstChild)

           

    defgetText(self,node):

        if node.nodeType == Node.TEXT_NODE :

            return node.nodeValue

        else: return""

       

    defhandle_author(self,node):

        author = node.firstChild

        for child inauthor.childNodes:

            if child.nodeType == Node.ELEMENT_NODE:

               if child.tagName=="firstname" :

                   print "Firstname : ",self.getText(child.firstChild)

               if child.tagName=="lastname" :

                   print "Lastname : ", self.getText(child.firstChild)

   

   

doc =minidom.parse("book.xml")

for child in doc.childNodes :

    ifchild.nodeType ==Node.COMMENT_NODE:

        print "Conment : ", child.nodeValue

    ifchild.nodeType ==Node.ELEMENT_NODE:

        bookscanner(child)

　　

输出结果：

Conment : This is a simple xml.
********************
Book id : 1001
Title : An apple
Firstname : Peter
Lastname : Zhang
Pubdate : 2012-1-12
********************
Book id : 1002
Title : Love
Firstname : Mike
Lastname : Li
Pubdate : 2012-1-10
********************
Book id : 1003
Title : Steve.Jobs
Firstname : Tom
Lastname : Wang
Pubdate : 2012-1-19
********************
Book id : 1004
Title : Harry Potter
Firstname : Peter
Lastname : Chen
Pubdate : 2012-11-11