python数据交换模块-XML

XML 可扩展标记语言

xml是实现不同语言或程序之间进行数据交换的协议，跟json差不多，但json使用起来更简单，不过，古时候，在json还没诞生的黑暗年代，大家只能选择用xml呀，至今很多传统公司如金融行业的很多系统的接口还主要是xml。

xml的格式如下，就是通过<>节点来区别数据结构的:

<?xml version="1.0"?>
<data>
        <country personinfo="Liechtenstein">
                <rank updated="yes">2</rank>
                <year>2008</year>
                <gdppc>141100</gdppc>
                <neighbor personinfo="Austria" direction="E"/>
                <neighbor personinfo="Switzerland" direction="W"/>
        </country>
        <country personinfo="Singapore">
                <rank updated="yes">5</rank>
                <year>2011</year>
                <gdppc>59900</gdppc>
                <neighbor personinfo="Malaysia" direction="N"/>
        </country>
        <country personinfo="Panama">
                <rank updated="yes">69</rank>
                <year>2011</year>
                <gdppc>13600</gdppc>
                <neighbor personinfo="Costa Rica" direction="W"/>
                <neighbor personinfo="Colombia" direction="E"/>
        </country>
</data>

xml协议在各个语言里的都是支持的，在python中可以用以下模块操作xml 　

import xml.etree.ElementTree as ET   #导入模块别名为ET
tree = ET.parse("xml-test.xml")    #打开xml-test.xml文件
root = tree.getroot()
print(root)             #是一个内存地址
print(root.tag)         #是xml文件的tag

#遍历xml文档
for child in root:
        print(child.tag,child.attrib,child.text)
        for i in child:
                print(i.tag,i.text,i.attrib)

#只遍历year节点
for node in root.iter("year"):
        print(node.tag,node.text)

修改和删除xml文档内容
import xml.etree.ElementTree as ET

tree = ET.parse("xmltest.xml")
root = tree.getroot()

#修改
for node in root.iter('year'):      #只遍历iter
        new_year = int(node.text) + 1
        node.text = str(new_year)
        node.set("updated","yes")

tree.write("xmltest.xml")

#删除node
for country in root.findall('country'):
     rank = int(country.find('rank').text)
     if rank > 50:
         root.remove(country)

tree.write('output.xml')

自己创建xml文档

import xml.etree.ElementTree as ET

new_xml = ET.Element("personinfolist")        #根节点
personinfo = ET.SubElement(new_xml,"personinfo",attrib={"enrolled":"yes"}) #new_xml子节点、节点名字、节点属性
name = ET.SubElement(personinfo,"name")
name.text = "aaa li"
age = ET.SubElement(personinfo,"age",attrib={"checked":"no"}) #
sex = ET.SubElement(personinfo,"sex")
age.text = '33'

personinfo2 = ET.SubElement(new_xml,"personinfo",attrib={"enrolled":"no"})
name2 = ET.SubElement(personinfo2,"name")
name2.text = "aaa wang"
age = ET.SubElement(personinfo2,"age")
age.text = '19'

et = ET.ElementTree(new_xml) #生成文档对象
et.write("test.xml", encoding="utf-8",xml_declaration=True)

ET.dump(new_xml) #打印生成的格式

结果：
<?xml version='1.0' encoding='utf-8'?>
<personinfolist>
    <personinfo enrolled="yes">
        <name>aaa li</name>
        <age checked="no">33</age>
        <sex />
    </personinfo>
    <personinfo enrolled="no">
        <name>aaa wang</name>
        <age>19</age>
    </personinfo>

</personinfolist>

本文转自506554897 51CTO博客，原文链接：，如需转载请自行联系原作者 http://blog.51cto.com/506554897/2047335