Python+Xml +操作+增删改查

<?xml version='1.0' encoding='utf-8'?>
<flags>
    <flag name="execute" value="false" />
    <flag name="other" value="value" />
</flags>

#!usr/bin/env python
#coding:utf-8
__author__='fangtao'
from xml.etree.ElementTree import ElementTree,Element  

class XmlDao():

    @staticmethod
    def openXml(filename):
        tree = ElementTree()  
        tree.parse(filename) 
        return tree
    @staticmethod
    def saveAs(tree,outfile):
        tree.write(outfile, encoding="utf-8",xml_declaration=True) 

    @staticmethod
    def add_child_node(nodelist, element):  
        '''给一个节点添加子节点 
           nodelist: 节点列表 
           element: 子节点''' 
        print len(nodelist) 
        print element
        for node in nodelist:  
            node.append(element)

    @staticmethod    
    def del_node_by_tagkeyvalue(nodelist, tag, kv_map):  
        '''同过属性及属性值定位一个节点，并删除之 
           nodelist: 父节点列表 
           tag:子节点标签 
           kv_map: 属性及属性值列表'''  
        for parent_node in nodelist:  
            children = parent_node.getchildren()  
            for child in children:  
                if child.tag == tag and XmlDao.if_match(child, kv_map):  
                    parent_node.remove(child)  
    @staticmethod    
    def create_node(tag, property_map, content=''):  
        '''新造一个节点 
           tag:节点标签 
           property_map:属性及属性值map 
           content: 节点闭合标签里的文本内容 
           return 新节点'''  
        element = Element(tag, property_map)  
        element.text = content  
        return element 
    @staticmethod
    def change_node_text(nodelist, text, is_add=False, is_delete=False):  
        '''改变/增加/删除一个节点的文本 
           nodelist:节点列表 
           text : 更新后的文本'''  
        for node in nodelist:  
            if is_add:  
                node.text += text  
            elif is_delete:  
                node.text = ""  
            else:  
                node.text = text
    @staticmethod  
    def change_node_properties(nodelist, kv_map, is_delete=False):  
        '''修改/增加 /删除 节点的属性及属性值 
           nodelist: 节点列表 
           kv_map:属性及属性值map'''  
        for node in nodelist:  
            for key in kv_map:  
                if is_delete:   
                    if key in node.attrib:  
                        del node.attrib[key]  
                else:  
                    node.set(key, kv_map.get(key)) 
    @staticmethod
    def get_node_by_keyvalue(nodelist, kv_map):  
        '''根据属性及属性值定位符合的节点，返回节点 
           nodelist: 节点列表 
           kv_map: 匹配属性及属性值map'''  
        result_nodes = []  
        for node in nodelist:  
            if XmlDao.if_match(node, kv_map):  
                result_nodes.append(node)  
        return result_nodes 
    @staticmethod
    def find_nodes(tree, path):  
        '''查找某个路径匹配的所有节点 
           tree: xml树 
           path: 节点路径'''  
        return tree.findall(path)
    @staticmethod
    def if_match(node, kv_map):  
        '''判断某个节点是否包含所有传入参数属性 
           node: 节点 
           kv_map: 属性及属性值组成的map'''  
        for key in kv_map:  
            if node.get(key) != kv_map.get(key):  
                return False  
        return True  

#!usr/bin/env python
#coding:utf-8
import XmlDao

class FlagDao():

    def __init__(self,filename=None):
        if filename is None:
            self.__filename = '../grapdata/flag.xml'
        else:
            self.__filename = filename
    #获取节点属性
    def getValueByName(self,name):
        tree = XmlDao.openXml(self.__filename)
        print 'tree',tree,self.__filename
        if tree is None:
            return None
        nodes = XmlDao.find_nodes(tree, 'flag')
        nodes = XmlDao.get_node_by_keyvalue(nodes, {'name':name})
        if len(nodes) > 0:
            return nodes[0].attrib['value']
        return None
    #设置节点
    def setValueByName(self,name,value):
        tree = XmlDao.openXml(self.__filename)
        if tree is None:
            return None
        nodes = XmlDao.find_nodes(tree, 'flag')
        nodes = XmlDao.get_node_by_keyvalue(nodes, {'name':name})
        if len(nodes) > 0:
            nodes[0].attrib['value'] = value
            XmlDao.saveAs(tree, self.__filename)
    #添加节点 
    def addTag(self,name,value):
        tree = XmlDao.openXml(self.__filename)
        XmlDao.add_child_node([tree.getroot()],XmlDao.create_node('flag', {'name':name,'value':value}))
        XmlDao.saveAs(tree, self.__filename) 
    #删除节点
    def deleteTagByName(self,name):
        tree = XmlDao.openXml(self.__filename)
        XmlDao.del_node_by_tagkeyvalue([tree.getroot()], 'flag', {'name':name})
        XmlDao.saveAs(tree, self.__filename)

import FlagDao

flagDao = FlagDao()

#查找节点
print flagDao.getValueByName('execute')
#修改节点
flagDao.setValueByName('execute', 'false')
#打印修改的节点
print flagDao.getValueByName('execute')
#添加节点
flagDao.addTag('zhangcan', 'bendan')
#删除节点
flagDao.deleteTagByName('other')

<?xml version='1.0' encoding='utf-8'?>
<flags>
    <flag name="execute" value="false" />
    <flag name="zhangcan" value="bendan" /></flags>