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<?xml version="1.0" encoding="ISO-8859-1"?><!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1" /><link rel="SHORTCUT ICON" href="/favicon.ico" /><style type="text/css">TD {font-family: Verdana,Arial,Helvetica}BODY {font-family: Verdana,Arial,Helvetica; margin-top: 2em; margin-left: 0em; margin-right: 0em}H1 {font-family: Verdana,Arial,Helvetica}H2 {font-family: Verdana,Arial,Helvetica}H3 {font-family: Verdana,Arial,Helvetica}A:link, A:visited, A:active { text-decoration: underline }</style><title>Python and bindings</title></head><body bgcolor="#8b7765" text="#000000" link="#a06060" vlink="#000000"><table border="0" width="100%" cellpadding="5" cellspacing="0" align="center"><tr><td width="120"><a href="http://swpat.ffii.org/"><img src="epatents.png" alt="Action against software patents" /></a></td><td width="180"><a href="http://www.gnome.org/"><img src="gnome2.png" alt="Gnome2 Logo" /></a><a href="http://www.w3.org/Status"><img src="w3c.png" alt="W3C Logo" /></a><a href="http://www.redhat.com/"><img src="redhat.gif" alt="Red Hat Logo" /></a><div align="left"><a href="http://xmlsoft.org/"><img src="Libxml2-Logo-180x168.gif" alt="Made with Libxml2 Logo" /></a></div></td><td><table border="0" width="90%" cellpadding="2" cellspacing="0" align="center" bgcolor="#000000"><tr><td><table width="100%" border="0" cellspacing="1" cellpadding="3" bgcolor="#fffacd"><tr><td align="center"><h1>The XML C parser and toolkit of Gnome</h1><h2>Python and bindings</h2></td></tr></table></td></tr></table></td></tr></table><table border="0" cellpadding="4" cellspacing="0" width="100%" align="center"><tr><td bgcolor="#8b7765"><table border="0" cellspacing="0" cellpadding="2" width="100%"><tr><td valign="top" width="200" bgcolor="#8b7765"><table border="0" cellspacing="0" cellpadding="1" width="100%" bgcolor="#000000"><tr><td><table width="100%" border="0" cellspacing="1" cellpadding="3"><tr><td colspan="1" bgcolor="#eecfa1" align="center"><center><b>Developer Menu</b></center></td></tr><tr><td bgcolor="#fffacd"><form action="search.php" enctype="application/x-www-form-urlencoded" method="get"><input name="query" type="text" size="20" value="" /><input name="submit" type="submit" value="Search ..." /></form><ul><li><a href="index.html" style="font-weight:bold">Main Menu</a></li><li><a href="html/index.html" style="font-weight:bold">Reference Manual</a></li><li><a href="examples/index.html" style="font-weight:bold">Code Examples</a></li><li><a href="guidelines.html">XML Guidelines</a></li><li><a href="tutorial/index.html">Tutorial</a></li><li><a href="xmlreader.html">The Reader Interface</a></li><li><a href="ChangeLog.html">ChangeLog</a></li><li><a href="XSLT.html">XSLT</a></li><li><a href="python.html">Python and bindings</a></li><li><a href="architecture.html">libxml2 architecture</a></li><li><a href="tree.html">The tree output</a></li><li><a href="interface.html">The SAX interface</a></li><li><a href="xmlmem.html">Memory Management</a></li><li><a href="xmlio.html">I/O Interfaces</a></li><li><a href="library.html">The parser interfaces</a></li><li><a href="entities.html">Entities or no entities</a></li><li><a href="namespaces.html">Namespaces</a></li><li><a href="upgrade.html">Upgrading 1.x code</a></li><li><a href="threads.html">Thread safety</a></li><li><a href="DOM.html">DOM Principles</a></li><li><a href="example.html">A real example</a></li><li><a href="xml.html">flat page</a>, <a href="site.xsl">stylesheet</a></li></ul></td></tr></table><table width="100%" border="0" cellspacing="1" cellpadding="3"><tr><td colspan="1" bgcolor="#eecfa1" align="center"><center><b>API Indexes</b></center></td></tr><tr><td bgcolor="#fffacd"><ul><li><a href="APIchunk0.html">Alphabetic</a></li><li><a href="APIconstructors.html">Constructors</a></li><li><a href="APIfunctions.html">Functions/Types</a></li><li><a href="APIfiles.html">Modules</a></li><li><a href="APIsymbols.html">Symbols</a></li></ul></td></tr></table><table width="100%" border="0" cellspacing="1" cellpadding="3"><tr><td colspan="1" bgcolor="#eecfa1" align="center"><center><b>Related links</b></center></td></tr><tr><td bgcolor="#fffacd"><ul><li><a href="http://mail.gnome.org/archives/xml/">Mail archive</a></li><li><a href="http://xmlsoft.org/XSLT/">XSLT libxslt</a></li><li><a href="http://phd.cs.unibo.it/gdome2/">DOM gdome2</a></li><li><a href="http://www.aleksey.com/xmlsec/">XML-DSig xmlsec</a></li><li><a href="ftp://xmlsoft.org/">FTP</a></li><li><a href="http://www.zlatkovic.com/projects/libxml/">Windows binaries</a></li><li><a href="http://www.blastwave.org/packages.php/libxml2">Solaris binaries</a></li><li><a href="http://www.zveno.com/open_source/libxml2xslt.html">MacOsX binaries</a></li><li><a href="http://sourceforge.net/projects/libxml2-pas/">Pascal bindings</a></li><li><a href="http://bugzilla.gnome.org/buglist.cgi?product=libxml2">Bug Tracker</a></li></ul></td></tr></table></td></tr></table></td><td valign="top" bgcolor="#8b7765"><table border="0" cellspacing="0" cellpadding="1" width="100%"><tr><td><table border="0" cellspacing="0" cellpadding="1" width="100%" bgcolor="#000000"><tr><td><table border="0" cellpadding="3" cellspacing="1" width="100%"><tr><td bgcolor="#fffacd"><p>There are a number of language bindings and wrappers available forlibxml2, the list below is not exhaustive. Please contact the <a href="http://mail.gnome.org/mailman/listinfo/xml-bindings">xml-bindings@gnome.org</a>(<a href="http://mail.gnome.org/archives/xml-bindings/">archives</a>) inorder to get updates to this list or to discuss the specific topic of libxml2or libxslt wrappers or bindings:</p><ul><li><a href="http://libxmlplusplus.sourceforge.net/">Libxml++</a> seems the most up-to-date C++ bindings for libxml2, check the <a href="http://libxmlplusplus.sourceforge.net/reference/html/hierarchy.html">documentation</a> and the <a href="http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/libxmlplusplus/libxml%2b%2b/examples/">examples</a>.</li> <li>There is another <a href="http://libgdome-cpp.berlios.de/">C++ wrapper based on the gdome2 bindings</a> maintained by Tobias Peters.</li> <li>and a third C++ wrapper by Peter Jones <pjones@pmade.org> <p>Website: <a href="http://pmade.org/pjones/software/xmlwrapp/">http://pmade.org/pjones/software/xmlwrapp/</a></p> </li> <li><a href="http://mail.gnome.org/archives/xml/2001-March/msg00014.html">Matt Sergeant</a> developed <a href="http://axkit.org/download/">XML::LibXSLT</a>, a Perl wrapper for libxml2/libxslt as part of the <a href="http://axkit.com/">AxKit XML application server</a>.</li> <li>If you're interested into scripting XML processing, have a look at <a href="http://xsh.sourceforge.net/">XSH</a> an XML editing shell based on Libxml2 Perl bindings.</li> <li><a href="mailto:dkuhlman@cutter.rexx.com">Dave Kuhlman</a> provides an earlier version of the libxml/libxslt <a href="http://www.rexx.com/~dkuhlman">wrappers for Python</a>.</li> <li>Gopal.V and Peter Minten develop <a href="http://savannah.gnu.org/projects/libxmlsharp">libxml#</a>, a set of C# libxml2 bindings.</li> <li>Petr Kozelka provides <a href="http://sourceforge.net/projects/libxml2-pas">Pascal units to glue libxml2</a> with Kylix, Delphi and other Pascal compilers.</li> <li>Uwe Fechner also provides <a href="http://sourceforge.net/projects/idom2-pas/">idom2</a>, a DOM2 implementation for Kylix2/D5/D6 from Borland.</li> <li>Wai-Sun "Squidster" Chia provides <a href="http://www.rubycolor.org/arc/redist/">bindings for Ruby</a> and libxml2 bindings are also available in Ruby through the <a href="http://libgdome-ruby.berlios.de/">libgdome-ruby</a> module maintained by Tobias Peters.</li> <li>Steve Ball and contributors maintains <a href="http://tclxml.sourceforge.net/">libxml2 and libxslt bindings for Tcl</a>.</li> <li>There is support for libxml2 in the DOM module of PHP.</li> <li><a href="http://savannah.gnu.org/projects/classpathx/">LibxmlJ</a> is an effort to create a 100% JAXP-compatible Java wrapper for libxml2 and libxslt as part of GNU ClasspathX project.</li> <li>Patrick McPhee provides Rexx bindings fof libxml2 and libxslt, look for <a href="http://www.interlog.com/~ptjm/software.html">RexxXML</a>.</li> <li><a href="http://www.satimage.fr/software/en/xml_suite.html">Satimage</a> provides <a href="http://www.satimage.fr/software/en/downloads_osaxen.html">XMLLib osax</a>. This is an osax for Mac OS X with a set of commands to implement in AppleScript the XML DOM, XPATH and XSLT. Also includes commands for Property-lists (Apple's fast lookup table XML format.)</li> <li>Francesco Montorsi developped<a href="https://sourceforge.net/project/showfiles.php?group_id=51305&package_id=45182">wxXml2</a> wrappers that interface libxml2, allowing wxWidgets applications to load/save/edit XML instances.</li></ul><p>The distribution includes a set of Python bindings, which are guaranteedto be maintained as part of the library in the future, though the Pythoninterface have not yet reached the completeness of the C API.</p><p><a href="mailto:stephane.bidoul@softwareag.com">St閜hane Bidoul</a>maintains <a href="http://users.skynet.be/sbi/libxml-python/">a Windows portof the Python bindings</a>.</p><p>Note to people interested in building bindings, the API is formalized as<a href="libxml2-api.xml">an XML API description file</a> which allows toautomate a large part of the Python bindings, this includes functiondescriptions, enums, structures, typedefs, etc... The Python script used tobuild the bindings is python/generator.py in the source distribution.</p><p>To install the Python bindings there are 2 options:</p><ul><li>If you use an RPM based distribution, simply install the <a href="http://rpmfind.net/linux/rpm2html/search.php?query=libxml2-python">libxml2-python RPM</a> (and if needed the <a href="http://rpmfind.net/linux/rpm2html/search.php?query=libxslt-python">libxslt-python RPM</a>).</li> <li>Otherwise use the <a href="ftp://xmlsoft.org/python/">libxml2-python module distribution</a> corresponding to your installed version of libxml2 and libxslt. Note that to install it you will need both libxml2 and libxslt installed and run "python setup.py build install" in the module tree.</li></ul><p>The distribution includes a set of examples and regression tests for thepython bindings in the <code>python/tests</code> directory. Here are someexcerpts from those tests:</p><h3>tst.py:</h3><p>This is a basic test of the file interface and DOM navigation:</p><pre>import libxml2, sysdoc = libxml2.parseFile("tst.xml")if doc.name != "tst.xml": print "doc.name failed" sys.exit(1)root = doc.childrenif root.name != "doc": print "root.name failed" sys.exit(1)child = root.childrenif child.name != "foo": print "child.name failed" sys.exit(1)doc.freeDoc()</pre><p>The Python module is called libxml2; parseFile is the equivalent ofxmlParseFile (most of the bindings are automatically generated, and the xmlprefix is removed and the casing convention are kept). All node seen at thebinding level share the same subset of accessors:</p><ul><li><code>name</code> : returns the node name</li> <li><code>type</code> : returns a string indicating the node type</li> <li><code>content</code> : returns the content of the node, it is based on xmlNodeGetContent() and hence is recursive.</li> <li><code>parent</code> , <code>children</code>, <code>last</code>, <code>next</code>, <code>prev</code>, <code>doc</code>, <code>properties</code>: pointing to the associated element in the tree, those may return None in case no such link exists.</li></ul><p>Also note the need to explicitly deallocate documents with freeDoc() .Reference counting for libxml2 trees would need quite a lot of work tofunction properly, and rather than risk memory leaks if not implementedcorrectly it sounds safer to have an explicit function to free a tree. Thewrapper python objects like doc, root or child are them automatically garbagecollected.</p><h3>validate.py:</h3><p>This test check the validation interfaces and redirection of errormessages:</p><pre>import libxml2#deactivate error messages from the validationdef noerr(ctx, str): passlibxml2.registerErrorHandler(noerr, None)ctxt = libxml2.createFileParserCtxt("invalid.xml")ctxt.validate(1)ctxt.parseDocument()doc = ctxt.doc()valid = ctxt.isValid()doc.freeDoc()if valid != 0: print "validity check failed"</pre><p>The first thing to notice is the call to registerErrorHandler(), itdefines a new error handler global to the library. It is used to avoid seeingthe error messages when trying to validate the invalid document.</p><p>The main interest of that test is the creation of a parser context withcreateFileParserCtxt() and how the behaviour can be changed before callingparseDocument() . Similarly the informations resulting from the parsing phaseare also available using context methods.</p><p>Contexts like nodes are defined as class and the libxml2 wrappers maps theC function interfaces in terms of objects method as much as possible. The⌨️ 快捷键说明
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