Python XML grooming

Import ElementTree Module

Import Xml.etree.ElementTree as ET

To create an element instance, use the element constructor or the subelement () factory function.
Et. Element (): Typically used to create a root node
Et. Subelement (): Used to create child nodes

The ElementTree class can be used to wrap an element structure for conversion to and from XML.

Commonly used:
ElementTree traverse the entire document.
Element iterates over a single node or a child node is usually used.

element: Method and function tag = Noneattrib = Nonetext = Nonetail = None def append (self, sub Element): Def extend (self, elements): def insert (self, Index, subelement): Def remove (self, subelement): def G    Etchildren (self): def find (self, Path, namespaces=none): Def findtext (self, path, Default=none, Namespaces=none): def findall (self, Path, Namespaces=none): def-iterfind (self, Path, Namespaces=none): Def Clear (self): def get (SE    LF, key, Default=none): Def set (self, key, value): Def keys: def items (self): def iter (self, tag=none): def itertext (self): 

ElementTree: Common function    def getroot (self):     def parse (self, source, Parser=none):  #打开xml文件    def iter (self, Tag=none):    def getiterator (self, Tag=none): def-    find (self, Path, Namespaces=none):    def-FindText (self, Path, Default=none, Namespaces=none):    def findall (self, Path, Namespaces=none):    def iterfind (self, path, Namespaces=none):    def write (self, file_or_filename,              Encoding=none,              Xml_declaration=none,              Default_namespace=none,              method=none, *,              short_empty_elements=true):

First, parse (get to root node [Element])
1. STR mode:
node = ET. XML (Str_xml) = et.fromstring (str_xml) #获取到根节点 (Element)
#XML () =fromstring ()
2. File Method:
result = Et.parse ("File.xml") # Open file, (ElementTree)
root = Result.getroot () # gets to the root node, (Element)

Ii. modification (use of [Element] type Object)
tag, attrib, text, find, ITER, remove, set ...

Third, re-write the file

Write must use the ElementTree object to invoke the Write method operation.
1, str parsing method to write files

node = ET. XML (str_xml) #获取到根节点 ... Operation et = et. ElementTree (Root) #创建一个tree et.write ("File.xml", encoding= "Utf-8", Xml_declaration=true) #写入文件

2, file method write back file

result = Et.parse ("File.xml") #获取Tree root = Result.getroot () #获取到根节点 ... Modify Result.write ("File.xml", encoding= "Utf-8", xml_declaration=true) writeback file

Iv. Creating an XML file

Element #创建根节点
subelement # Creating child nodes
ElementTree # Creating a tree for writing to a file

Five, indentation

Import Minidom Module
From Xml.dom import Minidom
When writing to a file is not using the tree, use the following code (where root is element and node)

c = Minidom.parsestring (et.tostring (Root, encoding= "Utf-8")). Toprettyxml (indent= "\ T") F = open ("File.xml", "W", encoding= "Utf-8") F.write (c) f.close () 

For the above operations, you can define a function to use:

def wrap (root): a = et.tostring (root, encoding= "Utf-8") B = minidom.parsestring (a) c = b.toprettyxml (indent= "\ T") Return C

Vi. namespaces

1. Register the namespace:

Et.register_namespace ("com", "http://www.ehaomiao.com")

2. Call (join before the label needs to use the namespace, format {}) as follows:

School = ET. Element ("{http://www.ehaomiao.com}school") University = ET. Subelement (School, "{http://www.ehaomiao.com}university", attrib={"Time": "4"})

3. Results
The root node is displayed as follows: (one more sentence xmlns:com= "http://www.ehaomiao.com")
<com:school xmlns:com= "http://www.ehaomiao.com" >
The nodes in each call namespace are displayed as follows: (more than one COM: flag)
<com:university time= "4" >

Vii. Important

You can use the type () method to see if you encounter problems with object types during the operation.

Viii. creating an XML file exercise

#!/usr/bin/env python#-*-coding:utf-8-*-# @Time: 2017/12/1 0001 14:07# @Author: MingimportXml.etree.ElementTree as Etfrom xml.dom importMinidomet.register_namespace ("com", "http://www.ehaomiao.com") # Register namespaceSchool = ET. Element ("{http://www.ehaomiao.com}school") # Call Namespace University = ET. Subelement (School, "{http://www.ehaomiao.com}university", attrib={"Time": "4"}) D1 = ET. Subelement (University, "D1") # University is its father node D1.text = "Freshman"D2 = ET. Subelement (University, "D2") D2.text = "Sophomore"D3 = ET. Subelement (University, "D3") D3.text = "Juniors"D4 = ET. Subelement (University, "D4") D4.text = "Seniors"High_school = ET. Subelement (School, "{Http://www.ehaomiao.com}high_school", attrib={"Time": "3"}) G1 = ET. Subelement (High_school, "G1") G1.text = "Freshman"G2 = ET. Subelement (High_school, "G2") G2.text = "Sophomore" g3 = ET. Subelement (High_school, "G3" ) G3.text = "Senior"  Middle_school = ET. Subelement (School, "{Http://www.ehaomiao.com}middle_school", attrib={"Time": "3" }) C1 = ET. Subelement (Middle_school, "C1" ) C1.text = "The Junior"  C2 = ET. Subelement (Middle_school, "C2" ) C2.text = "The Junior"  C3 = ET. Subelement (Middle_school, "C3" ) C3.text = "The" # writes the file without indentation, writes to the file1.xml file et =  et. ElementTree (School) et.write ("File1.xml", encoding= "utf=8", xml_declaration=  True) def  Wrap (Root): "" " Add a newline character to all nodes of the XML file:p Aram root: Root node [element type]: return: Returns the string "" " a = et.tostring (root, encoding=" Utf-8 ") with indentation added  b =  minidom.parsestring (a) c = b.toprettyxml (indent= "\ T" ) return  C # write file has indentation, write to file2.xml file a =  Wrap (School) f = open ("File2.xml", "W", encoding= "Utf-8" ) F.write (a) f.close ()     

<?XML version= "1.0"?><Com:schoolxmlns:com= "Http://www.ehaomiao.com">    <com:university Time= "4">        <D1>Freshman</D1>        <D2>Sophomore</D2>        <D3>Junior</D3>        <D4>Senior</D4>    </com:university>    <Com:high_school Time= "3">        <G1>High</G1>        <G2>High school</G2>        <G3>Three</G3>    </Com:high_school>    <Com:middle_school Time= "3">        <C1>First</C1>        <C2>First</C2>        <C3>First</C3>    </Com:middle_school></Com:school>

File2.xml

<?XML version= ' 1.0 ' encoding= ' utf=8 '?><Com:schoolxmlns:com= "Http://www.ehaomiao.com"><com:university Time= "4"><D1>Freshman</D1><D2>Sophomore</D2><D3>Junior</D3><D4>Senior</D4></com:university><Com:high_school Time= "3"><G1>High</G1><G2>High school</G2><G3>Three</G3></Com:high_school><Com:middle_school Time= "3"><C1>First</C1><C2>First</C2><C3>First</C3></Com:middle_school></Com:school>

File1.xml

Python XML grooming