Python讲解之对象转XML方法详解

# -*- coding:UTF-8 -*-
'''''
Created on 2010-4-20
@author: 忧里修斯
'''
import xml.etree.ElementTree as ET
import xml.dom.minidom as minidom
from addrbook.domain import Person
class Converter(object):
  '''''
     实现Python对象与xml之间的相互转换
  '''
  root = None#根节点
  def __init__(self):
    pass
  @staticmethod
  def createRoot(rootTag):
    '''''
          创建根节点
    '''
    root = ET.Element(rootTag)
    return root
  @staticmethod
  def getXmlString(element,defaultEncoding='utf-8'):
    '''''
          根据节点返回格式化的xml字符串
    '''
    try:
      rough_string = ET.tostring(element, defaultEncoding)
      reparsed = minidom.parseString(rough_string)
      return reparsed.toprettyxml(indent=" " , encoding=defaultEncoding)
    except:
      print 'getXmlString:传入的节点不能正确转换为xml，请检查传入的节点是否正确'
      return ''
  @staticmethod
  def classToElements(classobj,rootTag=None):
    '''''
          根据传入的对象的实例，根据对象的属性生成节点，返回由节点组成的列表
    classobj：对象的实例
    rootTag：根节点名称
    '''
    attrs = None#保存对象的属性集
    elelist = []#节点列表
    try:
      attrs = classobj.__dict__.keys()#获取该对象的所有属性(即成员变量)
    except:
      print 'classToElements:传入的对象非法，不能正确获取对象的属性'
    if attrs != None and len(attrs) > 0:#属性存在
      for attr in attrs:
        attrvalue = getattr(classobj, attr)#属性值
        #属性节点
        attrE = ET.Element(attr)
        attrE.text = attrvalue
        #加入节点列表
        elelist.append(attrE)
    return elelist
  @staticmethod
  def classToXML(classobj,rootTag=None):
    '''''
    Python自定义模型类转换成xml，转换成功返回的是xml根节点，否则返回None
    classobj：对象的实例
    rootTag：根节点名称
    '''
    try:
      classname = classobj.__class__.__name__ #类名
      if rootTag != None:
        root = Converter.createRoot(rootTag)
      else:
        root = Converter.createRoot(classname)
      elelist = Converter.classToElements(classobj, rootTag)
      for ele in elelist:
        root.append(ele)
      return root
    except:
      print 'classToXML:转换出错，请检查的传入的对象是否正确'
      return None
  @staticmethod
  def collectionToXML(listobj,rootTag='list'):
    '''''
              集合（列表、元组、字典）转换为xml，转换成功返回的是xml根节点，否则返回None
    '''
    try:
      classname = listobj.__class__.__name__ #类名
      root = Converter.createRoot(rootTag)
      if isinstance(listobj, list) or isinstance(listobj, tuple):#列表或元组
        if len(listobj) >= 0:
          for obj in listobj:#迭代列表中的对象
            itemE = Converter.classToXML(obj)
            root.append(itemE)
      elif isinstance(listobj, dict):#字典
        if len(listobj) >= 0:
          for key in listobj:#迭代字典中的对象
            obj = listobj[key]
            itemE = Converter.classToXML(obj)
            itemE.set('key', key)
            root.append(itemE)
      else:
        print 'listToXML：转换错误，传入的对象：'+classname+'不是集合类型'
      return root
    except:
      print 'collectionToXML：转换错误，集合转换成xml失败'
      return None
if __name__ == '__main__':
  p1 = Person('dredfsam','男','133665')
  p2 = Person('dream','女','r')
  p3 = Person('得分','男','sdf')
  personList = {}
  personList['p1']= p1
  personList['p2']= p2
  personList['p3']= p3
#  personList.append(p1)
#  personList.append(p2)
#  personList.append(p3)
  root = Converter.collectionToXML(personList)
  print Converter.getXmlString(root)
#  plist = (p1,p2,p3)#{'name':'sdf'}
#  print type(plist)
#  print type(plist),isinstance(plist, list)