xml模块

1.xml格式

<?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>

2.操作xml文档

2.1查询

#!/usr/bin/env python
# -*- coding:utf-8 -*-
# Author: vita
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,i.attrib)

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

E:\PythonProject\python-test\venvP3\Scripts\python.exe E:/PythonProject/python-test/BasicGrammer/test.py
data
country {'name': 'Liechtenstein'}
rank 2 {'updated': 'yes'}
year 2008 {}
gdppc 141100 {}
neighbor None {'name': 'Austria', 'direction': 'E'}
neighbor None {'name': 'Switzerland', 'direction': 'W'}
country {'name': 'Singapore'}
rank 5 {'updated': 'yes'}
year 2011 {}
gdppc 59900 {}
neighbor None {'name': 'Malaysia', 'direction': 'N'}
country {'name': 'Panama'}
rank 69 {'updated': 'yes'}
year 2011 {}
gdppc 13600 {}
neighbor None {'name': 'Costa Rica', 'direction': 'W'}
neighbor None {'name': 'Colombia', 'direction': 'E'}
year 2008
year 2011
year 2011

Process finished with exit code 0

2.2修改

#!/usr/bin/env python
# -*- coding:utf-8 -*-
# Author: vita
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")

E:\PythonProject\python-test\venvP3\Scripts\python.exe E:/PythonProject/python-test/BasicGrammer/test.py

Process finished with exit code 0
查看文件内容
<data>
    <country name="Liechtenstein">
        <rank updated="yes">2</rank>
        <year updated="yes">2009</year>
        <gdppc>141100</gdppc>
        <neighbor direction="E" name="Austria" />
        <neighbor direction="W" name="Switzerland" />
    </country>
    <country name="Singapore">
        <rank updated="yes">5</rank>
        <year updated="yes">2012</year>
        <gdppc>59900</gdppc>
        <neighbor direction="N" name="Malaysia" />
    </country>
    <country name="Panama">
        <rank updated="yes">69</rank>
        <year updated="yes">2012</year>
        <gdppc>13600</gdppc>
        <neighbor direction="W" name="Costa Rica" />
        <neighbor direction="E" name="Colombia" />
    </country>
</data>

2.3删除

#!/usr/bin/env python
# -*- coding:utf-8 -*-
# Author: vita
import xml.etree.ElementTree as ET

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

查看output.xml
<data>
    <country name="Liechtenstein">
        <rank updated="yes">2</rank>
        <year updated="yes">2009</year>
        <gdppc>141100</gdppc>
        <neighbor direction="E" name="Austria" />
        <neighbor direction="W" name="Switzerland" />
    </country>
    <country name="Singapore">
        <rank updated="yes">5</rank>
        <year updated="yes">2012</year>
        <gdppc>59900</gdppc>
        <neighbor direction="N" name="Malaysia" />
    </country>
    </data>

2.4创建xml文档

#!/usr/bin/env python
# -*- coding:utf-8 -*-
# Author: vita
import xml.etree.ElementTree as ET

new_xml = ET.Element("namelist")
name = ET.SubElement(new_xml,"name",attrib={"enrolled":"yes"})
age = ET.SubElement(name,"age",attrib={"checked":"no"})
sex = ET.SubElement(name,"sex")
sex.text = '33'
name2 = ET.SubElement(new_xml,"name",attrib={"enrolled":"no"})
age = ET.SubElement(name2,"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

E:\PythonProject\python-test\venvP3\Scripts\python.exe E:/PythonProject/python-test/BasicGrammer/test.py
<namelist><name enrolled="yes"><age checked="no" /><sex>33</sex></name><name enrolled="no"><age>19</age></name></namelist>

Process finished with exit code 0
查看文件内容

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