Python Basic Knowledge value XML

I. XML content

<data>
<country name= "Liechtenstein" >
<rank updated= "Yes" >2</rank>
<year>2023</year>
<gdppc>141100</gdppc>
<neighbor direction= "E" name= "Austria"/>
<neighbor direction= "W" Name= "Switzerland"/>
</country>
<country name= "Singapore" >
<rank updated= "Yes" >5</rank>
<year>2026</year>
<gdppc>59900</gdppc>
<neighbor direction= "N" name= "Malaysia"/>
</country>
<country name= "Panama" >
<rank updated= "Yes" >69</rank>
<year>2026</year>
<gdppc>13600</gdppc>
<neighbor direction= "W" name= "Costa Rica"/>
<neighbor direction= "E" name= "Colombia"/>
</country>
</data>

1. Parsing XML

From Xml.etree import ElementTree as ET

#打开XML, read the contents of the XML

Str_xml = open ("Fisrt1.xml", ' R '). Read ()

#将字符串解析成XML对象

root = ET. XML (Str_xml)

2. Parsing XML documents directly

#直接解析XML文件
Str_xml = Et.parse ("Fisrt1.xml")

#获取XML文件的根节点
root = Str_xml.getroot ()


2. Manipulating XML files

A. Traversing all content in an XML document

From Xml.etree import ElementTree as ET

#直接解析XML文件
Str_xml = Et.parse ("Fisrt1.xml")

#获取XML文件的根节点
root = Str_xml.getroot ()

#顶层标签

Print (Root.tag)

#遍历XML文件的第二层标签
For child in Root:
    Print (Child.tag, child.attrib)

#遍历XML文件的第三层标签
    For Sub_child in child:
        Print (Sub_child.tag, sub_child.text)


B. Traversing a pointing node in an XML file

From Xml.etree import ElementTree as ET

#打开XML, read the contents of the XML

#直接解析XML文件
Str_xml = Et.parse ("Fisrt1.xml")

#获取XML文件的根节点
root = Str_xml.getroot ()

#顶层标签

Print (Root.tag)

For node in Root.iter ("year"):
    Print (Node.tag, node.text)


For node in Root.iter ("GDPPC"):
    Print (Node.tag, node.text)


C. Modifying the contents of a node
Because the content of the node is modified in memory, it does not affect the contents of the file. If you want to modify the contents of a file successfully, you need to save the result of the memory modification to a file

From Xml.etree import ElementTree as ET

#直接解析XML文件
Str_xml = Et.parse ("Fisrt1.xml")

#获取XML文件的根节点
root = Str_xml.getroot ()

#顶层标签
Print (Root.tag)

#修改节点的内容
For node in Root.iter ("year"):

    #将节点的内容自加1
    new_year = Int (node.text) + 1
    Node.text = str (new_year)

    #设置节点
    Node.set (' name ', ' HJW ')
    Node.set (' Age ', ' 18 ')

# Save the modified file
Tree = ET. ElementTree (Root)
Tree.write (' aa.xml ', encoding = ' utf-8 ')

D. Deleting a node

 from Xml.etree import elementtree as ET 
 
 #直接解析XML文件 
 Str_xml = Et.parse ("Fisrt1.xml") 
 
 # Gets the root node of the xml file 
 root = Str_xml.getroot () 
 
 #顶层标签 
 Print (root.tag) 
 
 #遍历data下的country下节点 
 for Country In Root.findall (' Country '): 
 #获取每个rank节点的内容 
 rank = Int (country.find (' rank '). Text) 
 
 If rank > 50: 
 #删除指定的country节点 
 Root.remove (country) 
 
 #保存修改后的内容 
 tree = ET. ElementTree (Root) 
 Tree.write (' Bb.xml ', encoding= ' utf-8 ') 
 
 
 3. Create XML 

From Xml.etree import ElementTree as ET

#创建根节点

root = ET. Element (' famliy ')

#创建节点大儿子
Son1 = ET. Element (' son ', {' name ': ' Child 1 '})
#创建节点小儿子
Son2 = ET. Element (' son ', {' name ': ' Child 2 '})

#在大儿子中创建孙子节点
Grandson1 = ET. Element (' grandson ', {' name ': ' Child 11 '})
Grandson2 = ET. Element ("grandson", {' name ': ' Child 12 '})

#把孙子添加到儿1中
Son1.append (Grandson1)
Son1.append (Grandson2)

#把儿子添加中根节点中
Root.append (Son1)
Root.append (Son2)

#b保存文件
Tree = ET. ElementTree (Root)
Tree.write (' new_son1.xml ', encoding = ' utf-8 ')

Python Basic Knowledge value XML