标准库 xml

xml处理模块

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:

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

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

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

import xml.etree.ElementTree as ET   tree = ET.parse("xmltest.xml") root = tree.getroot() print(root.tag)   #遍历xml文档 for child in root:     print(child.tag, child.attrib)     for i in child:         print(i.tag,i.text)   #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

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

import xml.etree.ElementTree as ET   tree = ET.parse("xmltest.xml") root = tree.getroot()   #修改 for node in root.iter('year'):     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

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22

import xml.etree.ElementTree as ET new_xml = ET.Element("namelist") personinfo = ET.SubElement(new_xml, "personinfo", attrib={"enrolled": "yes"}) name=ET.SubElement(personinfo,'name') name.text='tom' age = ET.SubElement(personinfo, "age", attrib={"checked": "no"}) sex = ET.SubElement(personinfo, "sex") age.text = '33' sex.text='male' personinfo2 = ET.SubElement(new_xml, "personinfo", attrib={"enrolled": "no"}) name=ET.SubElement(personinfo2,'name') name.text='tom' age = ET.SubElement(personinfo2, "age") sex = ET.SubElement(personinfo2, "sex") age.text = '19' sex.text='male' 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

 返回结果为：

<?xml version='1.0' encoding='utf-8'?>
<namelist>
    <personinfo enrolled="yes">
        <name>tom</name>
        <age checked="no">33</age>
        <sex>male</sex>
    </personinfo>
    <personinfo enrolled="no">
        <name>tom</name>
        <age>19</age>
        <sex>male</sex>
    </personinfo>
</namelist>