Python中使用dom模块生成XML文件示例

  在Python中解析XML文件也有Dom和Sax两种方式,这里先介绍如何是使用Dom解析XML,这一篇文章是Dom生成XML文件,下一篇文章再继续介绍Dom解析XML文件。

  在生成XML文件中,我们主要使用下面的方法来完成。

  主要方法

  1、生成XML节点(node)

createElement("node_name")

  2、给节点添加属性值(Attribute)

node.setAttribute("att_name", "arr_value")

  3、节点的标签值(data)

createTextNode("node_value")

  

  其中第1、3点在创建完节点(节点值)之后,还需使用下面的方法添加到指点的节点的位置下面

prev_node.appendChild(cur_node)

  

这里的prev_node要添加节点的上一层节点,而cur_node即为当前要添加的节点了。

代码演示

下面用代码来演示下如何使用Dom来生成XML,这个是简单版本,如下:

'''
Created on 2012-8-28  
  
 @author:  walfred 
 @module: domxml.genXML  
 @description: 
 '''  
 import xml.dom.minidom as Dom  
  
 if __name__ == "__main__":  
     doc = Dom.Document()  
     root_node = doc.createElement("book_store")  
     root_node.setAttribute("name", "newhua")  
     root_node.setAttribute("website", "http://www.jb51.net")  
     doc.appendChild(root_node)  
  
     book_node = doc.createElement("book1")  
  
     book_name_node = doc.createElement("name")  
     book_name_value = doc.createTextNode("hamlet")  
     book_name_node.appendChild(book_name_value)  
     book_node.appendChild(book_name_node)  
  
     book_author_node = doc.createElement("author")  
     book_author_value = doc.createTextNode("William Shakespeare")  
     book_author_node.appendChild(book_author_value)  
     book_node.appendChild(book_author_node)  
  
     root_node.appendChild(book_node)  
  
     f = open("book_store.xml", "w")  
     f.write(doc.toprettyxml(indent = "	", newl = "
", encoding = "utf-8"))  
     f.close()

  这个代码将在当前目录下生成一个book_store.xml文件,我把它也贴在下面:

<?xml version="1.0" encoding="utf-8"?>  
 <book_store name="newhua" website="http://www.jb51.net">  
     <book1>  
         <name>hamlet</name>  
         <author>William Shakespeare</author>  
     </book1>  
 </book_store>

  当然一旦你掌握了这些基本方法之后,我们可以用一个类来更好的完成,这个类我们称之为XMLGenerator,代码如下:

''' 
Created on 2012-8-28  
  
 @author:  walfred 
 @module: domxml.wXMLbyDom  
 @description: 
 '''  
 import xml.dom.minidom as Dom  
  
 class XMLGenerator:  
     def __init__(self, xml_name):  
         self.doc = Dom.Document()  
         self.xml_name = xml_name  
  
     def createNode(self, node_name):  
         return self.doc.createElement(node_name)  
  
     def addNode(self, node, prev_node = None):  
         cur_node = node  
         if prev_node is not None:  
             prev_node.appendChild(cur_node)  
         else:  
             self.doc.appendChild(cur_node)  
         return cur_node  
  
     def setNodeAttr(self, node, att_name, value):  
         cur_node = node  
         cur_node.setAttribute(att_name, value)  
  
     def setNodeValue(self, cur_node, value):  
         node_data = self.doc.createTextNode(value)  
         cur_node.appendChild(node_data)  
  
     def genXml(self):  
         f = open(self.xml_name, "w")  
         f.write(self.doc.toprettyxml(indent = "	", newl = "
", encoding = "utf-8"))  
         f.close()  
  
 if __name__ == "__main__":  
     myXMLGenerator = XMLGenerator("book_store.xml")  
  
     #xml root node  
     node_book_store = myXMLGenerator.createNode("book_store")  
     myXMLGenerator.setNodeAttr(node_book_store, "name", "new hua")  
     myXMLGenerator.setNodeAttr(node_book_store, "website", "http://www.jb51.net")  
     myXMLGenerator.addNode(node = node_book_store)  
  
     #book01  
     node_book_01 = myXMLGenerator.createNode("book")  
  
     node_book_01_name = myXMLGenerator.createNode("name")  
     myXMLGenerator.setNodeValue(node_book_01_name, "Hamlet")  
     myXMLGenerator.addNode(node_book_01_name, node_book_01)  
  
     node_book_01_author = myXMLGenerator.createNode("author")  
     myXMLGenerator.setNodeValue(node_book_01_author, "William Shakespeare")  
     myXMLGenerator.addNode(node_book_01_author, node_book_01)  
  
     node_book_01_price = myXMLGenerator.createNode("price")  
     myXMLGenerator.setNodeValue(node_book_01_price, "$20")  
     myXMLGenerator.addNode(node_book_01_price, node_book_01)  
  
     node_book_01_grade = myXMLGenerator.createNode("grade")  
     myXMLGenerator.setNodeValue(node_book_01_grade, "good")  
     myXMLGenerator.addNode(node_book_01_grade, node_book_01)  
  
     myXMLGenerator.addNode(node_book_01, node_book_store)  
  
     #book 02  
     node_book_02 = myXMLGenerator.createNode("book")  
  
     node_book_02_name = myXMLGenerator.createNode("name")  
     myXMLGenerator.setNodeValue(node_book_02_name, "shuihu")  
     myXMLGenerator.addNode(node_book_02_name, node_book_02)  
  
     node_book_02_author = myXMLGenerator.createNode("author")  
     myXMLGenerator.setNodeValue(node_book_02_author, "naian shi")  
     myXMLGenerator.addNode(node_book_02_author, node_book_02)  
  
     node_book_02_price = myXMLGenerator.createNode("price")  
     myXMLGenerator.setNodeValue(node_book_02_price, "$200")  
     myXMLGenerator.addNode(node_book_02_price, node_book_02)  
  
     node_book_02_grade = myXMLGenerator.createNode("grade")  
     myXMLGenerator.setNodeValue(node_book_02_grade, "good")  
     myXMLGenerator.addNode(node_book_02_grade, node_book_02)  
  
     myXMLGenerator.addNode(node_book_02, node_book_store)  
  
     #gen  
     myXMLGenerator.genXml()

  同样这个方法会在本目录下生成一个book_store.xml文件,如下:

<?xml version="1.0" encoding="utf-8"?>  
 <book_store name="new hua" website="http://www.jb51.net">  
     <book>  
         <name>Hamlet</name>  
         <author>William Shakespeare</author>  
         <price>$20</price>  
         <grade>good</grade>  
     </book>  
     <book>  
         <name>shuihu</name>  
         <author>naian shi</author>  
         <price>$200</price>  
         <grade>good</grade>  
     </book>  
 </book_store>