Python+selenium Automated Software Testing (12th): Python reads and writes XML documents

XML Extensible Markup Language, which can be used to tag data, define data types, is a source language that allows users to define their own markup language.
XML has the following characteristics: First, it is tagged to the constituent:<aa></aa> tag can have attributes: <aa id= ' 123 ' ></aa> tag pair can embed data: <AA>ABC</AA >
Python often has several modules for XML document reading and writing:
(1) Xml.etree.ElementTree
ElementTree is like a lightweight dom, with a convenient and friendly API. Good code availability, fast speed, low memory consumption.
(2) xml.dom.*
Parses XML data into a tree in memory, manipulating the XML by manipulating the tree.
(3) xml.sax.*

The Python standard library contains the SAX parser, which uses the event-driven model to process XML files by triggering events and invoking user-defined callback functions during parsing of XML.

Writing to an XML document

#Coding:utf-8 fromXml.domImportMinidom#ways to write XML documentsdefcreate_xml_test (filename):#new XML Document ObjectXml=Minidom. Document ()#Create the first node, the first node is the root nodeRoot=xml.cneateelement ('Root')    #Write Property (Xmlns:xsi is a namespace and can also be written to xsi:schemalocation specify an XSD file)Root.setattribute ('Xmlns:xsi', 'http://www.xxx.com')    #After you create a node, you also need to add it to the document before it is validXml.appendchild (Root)#The general root node is rarely write text content, then create a child node for the root nodeText_node=xml.createelement ('element') Text_node.setattribute ('ID','ID1') Root.appendchild (Text_node)#add text to this node, and the text is a nodeText=xml.cneatetextnode ('Hello World') text_node.appendchild (text)#once a node has been added to the text, you can continue to append something elseTag=xml.createelement ('Tag') Tag.setattribute ('Data','Tag Data') Text_node.appendchild (tag)#Once you've written it, you'll need to save the document.F=open (filename,'W') F.write (Xml.toprettyxml (Encodings'Utf-8') ) F.close ()if __name__=='__main__':    #under current directory, create 1. XMLCreate_xml_test ('1.xml')

A copy of the XML document will be generated locally

Reading an XML document

#Coding:utf-8 fromXml.domImportMinidom#ways to read XML documentsdefread_xml_test (filename):#Open this document and parse it with the parse methodXML =minidom.parse (filename)#Get root nodeRoot =xml.documentelement#get all element nodes below the root node   #More methods can refer to the content of W3school or with Dir (root) to obtainelements = Root.getelementsbytagname ('element')   #traversal processing, elements is a list    forElementinchelements:#determine if there is an id attribute      ifElement.hasattribute ('ID'):         #you can not add the above judgment, if the property is not found, then return an empty         Print 'ID:, Element.getattribute ('Id')   #traversing the child nodes of element    forNodeinchElement.childnodes:#determine whether text is by Nodemame      ifNode.nodename = ='#text':         #get text content with the Data propertyText = Node.data.replace ('\ n,"')         #the text here needs special treatment, there will be extra \ n         PrintU'\ t Text:', TextElse:         #Output Node name         Print '\ t'+Node.nodename#output attribute values, which can be obtained using the GetAttribute method         #can also be traversed to get that this is a dictionary          forAttr,attr_valinchNode.attributes.items ():Print '\t\t', attr,':'Jattr_valPrint "'if __name__=='__main__': Read_xml_test ('Test.xml') Raw_input ('OK')

Python+selenium Automated Software Testing (12th): Python reads and writes XML documents