Python parsing xml file

python parsing of XML

The common XML programming interface has DOM and sax, and the two interfaces handle XML files in different ways, of course, using different scenarios.

Python has three ways to parse Xml,sax,dom, and ElementTree:

1.SAX (Simple API for XML)

The Pyhton 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.

2.DOM (Document Object Model)

Parses XML data into a tree in memory, manipulating the XML by manipulating the tree.

The file object model, or DOM, is the standard programming interface recommended by the Organization for the processing of extensible superscript languages.

A DOM parser parses an XML document, reads the entire document at once, stores all the elements of the document in a tree structure in memory, and then you can use the different functions provided by the DOM to read or modify the contents and structure of the document, or to write the modified content to an XML file.

3.ElementTree (element tree)

ElementTree is like a lightweight dom, with a convenient and friendly API. Good code availability, fast speed, low memory consumption.

1. Loading an XML file

There are 2 ways to load an XML file, one to load the specified string, and two to load the specified file

2. How to obtain the element

A) through Getiterator

b) Over GetChildren

C) Find method

D) FindAll method

Note: because the DOM needs to map XML data to a tree in memory, one is slower, the other is less memory, and Sax streams the XML file faster and consumes less memory, but requires the user to implement the callback function (handler).

# coding: utf-8# filename: testxml.py#  Method A test parse XML file, using Xml.dom mode import  Xml.dom.minidomxmlfile = r ' E:\Program\python\testxml.xml ' def testxmlusedom ():         domtree = xml.dom.minidom.parse (xmlfile)     #   Get root node     root = DOMTree.documentElement    #  Get Properties     if root.hasattribute ("shelf"):         print  "root element: %s"  % root.getattribute ("shelf")     #  Gets the child node     movies = root.getelementsbytagname ("movie")     for  move in movies:        print  "*****movie******"         if move.hasattribute ("Title"):             print  "movie : %s",  move.getattribute ("Title")       Text of the                #  node, data         t = move.getelementsbytagname ("type") [0]         print  "type: %s"  % t.childNodes[0].data                 f =  Move.getelementsbytagname ("format") [0]        print  "format:  %s " % f.childnodes[0].data        testxmlusedom () #   Method Two, using Elementtreefrom xml.etree import elementtree as etdef print_node ( node):     ' Print node '     print  ' ========================== '      #  return property is a dictionary format     print  "node.attrib: %s"  % node.attrib    if  Node.attrib.has_key ("title"):        print  "node.attrib[' title ']:  %s " % node.attrib[' title ']    # tag  node name      print  "node.tag:%s"  % node.tag    # text  node content      print  "node.text:%s"  % node.textdef testxmlet ():    print  " Testxmlet "    #  load file     root = et.parse (xmlfile)      #  Load from Text     # root = et.fromstring (text)      #  Traversing child nodes     lst_node = root.getiterator ("movie")      for node in lst_node:             print_node (node)     #  get the first node movie    print  "First movie:"      #  Get all child nodes getchildren    lst_node_child = lst_node[0]. GetChildren () [0]    print_node (Lst_node_child)     print  "find  movie: "    node_find = root.find (" movie ")     print_ Node (node_find)     # findall, find all     node_findall =  Root.findall ("movie") [1]    print_node (Node_findall)     #  Find     node_findone = root.find directly using the path ("Movie/type")     print_ Node (node_findone)     #  Direct use path lookup     node_findall2 =  Root.findall ("Movie/type")     for node in node_findall2:         print_Node (node_findone)         testxmlet () 

Python parsing xml file