标准库 xml | 易学教程

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:

<?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 　　

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

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

import xml.etree.ElementTree as ETnew_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>

来源：https://www.cnblogs.com/zoe233/p/7125187.html

标签

xml语言