Python Basics-Day 5 learning note-Standard library of modules: XML (9)

XML Module Introduction

As with JSON, protocols for data exchange in different languages and programs. But JSON is easier to use and has a tendency to replace XML. Now most financial data providers (e.g. Bloombegy) are still using XML.

In Python, generate and parse XML files with the import Xml.etree.ElementTree module

Format of the XML file

The format of XML is as follows: by the <> node to distinguish the data structure.

Format common operations for XML

Read XML

ImportXml.etree.ElementTree as Ettree= Et.parse ("Xmltest.xml") Root=tree.getroot ()Print(Root.tag)#Back to Data#Calendar XML Documents forChildinchRoot:Print(Child.tag, Child.attrib)#return to country layer     forIinchChild :Print(I.tag, I.text)#only calendar year node, select data Calendar forNodeinchRoot.iter (" Year"):    Print(Node.tag,node.text)

Read XML

Modify the contents of the delete XML file

ImportXml.etree.ElementTree as Ettree= Et.parse ("Xmltest.xml") Root=tree.getroot ()#Modifying Data forNodeinchRoot.iter (" Year"): New_year= Int (node.text) + 1#1 increase every yearNode.text = str (new_year)#Assign ValueNode.set ("Updated","Yes")#Also, modify the Attribution propertyTree.write ("Xmltest.xml")#Delete a node forCountryinchRoot.findall ("Country"): Rank= Int (Country.find ('Rank'). Text)ifRank > 50: Root.remove (country) tree.write ("Output.xml")

Modify and delete

Create a new XML file

ImportXml.etree.ElementTree as Etnew_xml= ET. Element ("NameList")#Creating the root nodePersoninfo = ET. Subelement (New_xml,"Personinfo", attrib={"enrolled":"yea"}) name= ET. Subelement (Personinfo,"name") Name.text="Alex Li" Age= ET. Subelement (Personinfo," Age", attrib={"checked":"No"}) Age.text=" About"Sex= ET. Subelement (Personinfo,"Sex") Sex.text="F"Personinfo2= ET. Subelement (New_xml,"Personinfo", attrib={"enrolled":"Yes"}) name= ET. Subelement (Personinfo2,"name") Name.text="Oldboy ran" Age= ET. Subelement (Personinfo2," Age") Age.text=" A"et= ET. ElementTree (New_xml)#Generating Document ObjectsEt.write ("New_xml_test.xml", encoding="Utf-8", xml_declaration=True) Et.dump (New_xml)#print the generated format

Create

Python Basics-Day 5 learning note-Standard library of modules: XML (9)