Python parses XML files
This article mainly introduces Python’s implementation ideas for XML file parsing. I hope it will be helpful to friends in need!
XML file parsing
Parsing ideas:
1.DOM parsing and SAX parsing, ET parsing ( Element tree)
First, it is xml.dom.* module, which is the implementation of W3C DOM API. If you need to process DOMAPI, this module is very suitable;
Second, it is xml.sax. *Module, which is an implementation of the SAX API. This module sacrifices convenience for speed and memory usage. SAX is an event-based API, which means that it can process a huge number of documents "in the air" without completely Load into memory;
Third, it is the xml.etree.ElementTree module (ET for short), which provides a lightweight Python-style API. Compared with DOM, ET is much faster and has many commands. A pleasant API can be used. Compared to SAX, ET's ET.iterparse also provides an "on-the-air" processing method. There is no need to load the entire document into memory. The average performance of ET is similar to that of SAX, but the efficiency of the API is A bit taller and easy to use.
2.1 xml.dom.*
The Document Object Model (DOM) is a standard programming interface recommended by the W3C organization for processing extensible markup languages. When a DOM parser parses an XML document, it reads the entire document at once and saves all the elements in the document in a tree structure in memory. You can then use the different functions provided by the DOM to read or modify the document. The content and structure can also be written into the xml file. Use xml.dom.minidom in python to parse xml files.
2.2 xml.etree.ElementTree
ElementTree was born to process XML. It has two implementations in the Python standard library:
1. Pure Python implementation, such as xml.etree.ElementTree,
Second, it is the faster xml.etree.cElementTree. Starting from Python 3.3, the ElementTree module will automatically search for available C libraries to speed up the process.
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