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HTMLParser — Simple HTML and XHTML parser — Python v2.6.6 documentation</title> <link rel="stylesheet" href="../_static/default.css" type="text/css" /> <link rel="stylesheet" href="../_static/pygments.css" type="text/css" /> <script type="text/javascript"> var DOCUMENTATION_OPTIONS = { URL_ROOT: '../', VERSION: '2.6.6', COLLAPSE_MODINDEX: false, FILE_SUFFIX: '.html', HAS_SOURCE: true }; </script> <script type="text/javascript" src="../_static/jquery.js"></script> <script type="text/javascript" src="../_static/doctools.js"></script> <link rel="search" type="application/opensearchdescription+xml" title="Search within Python v2.6.6 documentation" href="../_static/opensearch.xml"/> <link rel="author" title="About these documents" href="../about.html" /> <link rel="copyright" title="Copyright" href="../copyright.html" /> <link rel="top" title="Python v2.6.6 documentation" href="../index.html" /> <link rel="up" title="19. 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Structured Markup Processing Tools</a> »</li> </ul> </div> <div class="document"> <div class="documentwrapper"> <div class="bodywrapper"> <div class="body"> <div class="section" id="module-HTMLParser"> <h1>19.1. <tt class="xref docutils literal"><span class="pre">HTMLParser</span></tt> — Simple HTML and XHTML parser<a class="headerlink" href="#module-HTMLParser" title="Permalink to this headline">¶</a></h1> <div class="admonition note"> <p class="first admonition-title">Note</p> <p class="last">The <tt class="xref docutils literal"><span class="pre">HTMLParser</span></tt> module has been renamed to <tt class="xref docutils literal"><span class="pre">html.parser</span></tt> in Python 3.0. The <a class="reference external" href="../glossary.html#term-to3"><em class="xref">2to3</em></a> tool will automatically adapt imports when converting your sources to 3.0.</p> </div> <p class="versionadded"> <span class="versionmodified">New in version 2.2.</span></p> <p id="index-378">This module defines a class <a title="HTMLParser.HTMLParser" class="reference internal" href="#HTMLParser.HTMLParser"><tt class="xref docutils literal"><span class="pre">HTMLParser</span></tt></a> which serves as the basis for parsing text files formatted in HTML (HyperText Mark-up Language) and XHTML. Unlike the parser in <a title="A parser for HTML documents. (deprecated)" class="reference external" href="htmllib.html#module-htmllib"><tt class="xref docutils literal"><span class="pre">htmllib</span></tt></a>, this parser is not based on the SGML parser in <a title="Only as much of an SGML parser as needed to parse HTML. (deprecated)" class="reference external" href="sgmllib.html#module-sgmllib"><tt class="xref docutils literal"><span class="pre">sgmllib</span></tt></a>.</p> <dl class="class"> <dt id="HTMLParser.HTMLParser"> <em class="property">class </em><tt class="descclassname">HTMLParser.</tt><tt class="descname">HTMLParser</tt><a class="headerlink" href="#HTMLParser.HTMLParser" title="Permalink to this definition">¶</a></dt> <dd><p>The <a title="HTMLParser.HTMLParser" class="reference internal" href="#HTMLParser.HTMLParser"><tt class="xref docutils literal"><span class="pre">HTMLParser</span></tt></a> class is instantiated without arguments.</p> <p>An <a title="HTMLParser.HTMLParser" class="reference internal" href="#HTMLParser.HTMLParser"><tt class="xref docutils literal"><span class="pre">HTMLParser</span></tt></a> instance is fed HTML data and calls handler functions when tags begin and end. The <a title="HTMLParser.HTMLParser" class="reference internal" href="#HTMLParser.HTMLParser"><tt class="xref docutils literal"><span class="pre">HTMLParser</span></tt></a> class is meant to be overridden by the user to provide a desired behavior.</p> <p>Unlike the parser in <a title="A parser for HTML documents. (deprecated)" class="reference external" href="htmllib.html#module-htmllib"><tt class="xref docutils literal"><span class="pre">htmllib</span></tt></a>, this parser does not check that end tags match start tags or call the end-tag handler for elements which are closed implicitly by closing an outer element.</p> </dd></dl> <p>An exception is defined as well:</p> <dl class="exception"> <dt id="HTMLParser.HTMLParseError"> <em class="property">exception </em><tt class="descclassname">HTMLParser.</tt><tt class="descname">HTMLParseError</tt><a class="headerlink" href="#HTMLParser.HTMLParseError" title="Permalink to this definition">¶</a></dt> <dd>Exception raised by the <a title="HTMLParser.HTMLParser" class="reference internal" href="#HTMLParser.HTMLParser"><tt class="xref docutils literal"><span class="pre">HTMLParser</span></tt></a> class when it encounters an error while parsing. This exception provides three attributes: <tt class="xref docutils literal"><span class="pre">msg</span></tt> is a brief message explaining the error, <tt class="xref docutils literal"><span class="pre">lineno</span></tt> is the number of the line on which the broken construct was detected, and <tt class="xref docutils literal"><span class="pre">offset</span></tt> is the number of characters into the line at which the construct starts.</dd></dl> <p><a title="HTMLParser.HTMLParser" class="reference internal" href="#HTMLParser.HTMLParser"><tt class="xref docutils literal"><span class="pre">HTMLParser</span></tt></a> instances have the following methods:</p> <dl class="method"> <dt id="HTMLParser.HTMLParser.reset"> <tt class="descclassname">HTMLParser.</tt><tt class="descname">reset</tt><big>(</big><big>)</big><a class="headerlink" href="#HTMLParser.HTMLParser.reset" title="Permalink to this definition">¶</a></dt> <dd>Reset the instance. Loses all unprocessed data. This is called implicitly at instantiation time.</dd></dl> <dl class="method"> <dt id="HTMLParser.HTMLParser.feed"> <tt class="descclassname">HTMLParser.</tt><tt class="descname">feed</tt><big>(</big><em>data</em><big>)</big><a class="headerlink" href="#HTMLParser.HTMLParser.feed" title="Permalink to this definition">¶</a></dt> <dd>Feed some text to the parser. It is processed insofar as it consists of complete elements; incomplete data is buffered until more data is fed or <a title="HTMLParser.HTMLParser.close" class="reference internal" href="#HTMLParser.HTMLParser.close"><tt class="xref docutils literal"><span class="pre">close()</span></tt></a> is called.</dd></dl> <dl class="method"> <dt id="HTMLParser.HTMLParser.close"> <tt class="descclassname">HTMLParser.</tt><tt class="descname">close</tt><big>(</big><big>)</big><a class="headerlink" href="#HTMLParser.HTMLParser.close" title="Permalink to this definition">¶</a></dt> <dd>Force processing of all buffered data as if it were followed by an end-of-file mark. This method may be redefined by a derived class to define additional processing at the end of the input, but the redefined version should always call the <a title="HTMLParser.HTMLParser" class="reference internal" href="#HTMLParser.HTMLParser"><tt class="xref docutils literal"><span class="pre">HTMLParser</span></tt></a> base class method <a title="HTMLParser.HTMLParser.close" class="reference internal" href="#HTMLParser.HTMLParser.close"><tt class="xref docutils literal"><span class="pre">close()</span></tt></a>.</dd></dl> <dl class="method"> <dt id="HTMLParser.HTMLParser.getpos"> <tt class="descclassname">HTMLParser.</tt><tt class="descname">getpos</tt><big>(</big><big>)</big><a class="headerlink" href="#HTMLParser.HTMLParser.getpos" title="Permalink to this definition">¶</a></dt> <dd>Return current line number and offset.</dd></dl> <dl class="method"> <dt id="HTMLParser.HTMLParser.get_starttag_text"> <tt class="descclassname">HTMLParser.</tt><tt class="descname">get_starttag_text</tt><big>(</big><big>)</big><a class="headerlink" href="#HTMLParser.HTMLParser.get_starttag_text" title="Permalink to this definition">¶</a></dt> <dd>Return the text of the most recently opened start tag. This should not normally be needed for structured processing, but may be useful in dealing with HTML “as deployed” or for re-generating input with minimal changes (whitespace between attributes can be preserved, etc.).</dd></dl> <dl class="method"> <dt id="HTMLParser.HTMLParser.handle_starttag"> <tt class="descclassname">HTMLParser.</tt><tt class="descname">handle_starttag</tt><big>(</big><em>tag</em>, <em>attrs</em><big>)</big><a class="headerlink" href="#HTMLParser.HTMLParser.handle_starttag" title="Permalink to this definition">¶</a></dt> <dd><p>This method is called to handle the start of a tag. It is intended to be overridden by a derived class; the base class implementation does nothing.</p> <p>The <em>tag</em> argument is the name of the tag converted to lower case. The <em>attrs</em> argument is a list of <tt class="docutils literal"><span class="pre">(name,</span> <span class="pre">value)</span></tt> pairs containing the attributes found inside the tag’s <tt class="docutils literal"><span class="pre"><></span></tt> brackets. The <em>name</em> will be translated to lower case, and quotes in the <em>value</em> have been removed, and character and entity references have been replaced. For instance, for the tag <tt class="docutils literal"><span class="pre"><A</span> <span class="pre">HREF="http://www.cwi.nl/"></span></tt>, this method would be called as <tt class="docutils literal"><span class="pre">handle_starttag('a',</span> <span class="pre">[('href',</span> <span class="pre">'http://www.cwi.nl/')])</span></tt>.</p> <p class="versionchanged"> <span class="versionmodified">Changed in version 2.6: </span>All entity references from <a title="Definitions of HTML general entities." class="reference external" href="htmllib.html#module-htmlentitydefs"><tt class="xref docutils literal"><span class="pre">htmlentitydefs</span></tt></a> are now replaced in the attribute values.</p> </dd></dl> <dl class="method"> <dt id="HTMLParser.HTMLParser.handle_startendtag"> <tt class="descclassname">HTMLParser.</tt><tt class="descname">handle_startendtag</tt><big>(</big><em>tag</em>, <em>attrs</em><big>)</big><a class="headerlink" href="#HTMLParser.HTMLParser.handle_startendtag" title="Permalink to this definition">¶</a></dt> <dd>Similar to <a title="HTMLParser.HTMLParser.handle_starttag" class="reference internal" href="#HTMLParser.HTMLParser.handle_starttag"><tt class="xref docutils literal"><span class="pre">handle_starttag()</span></tt></a>, but called when the parser encounters an XHTML-style empty tag (<tt class="docutils literal"><span class="pre"><a</span> <span class="pre">.../></span></tt>). This method may be overridden by subclasses which require this particular lexical information; the default implementation simple calls <a title="HTMLParser.HTMLParser.handle_starttag" class="reference internal" href="#HTMLParser.HTMLParser.handle_starttag"><tt class="xref docutils literal"><span class="pre">handle_starttag()</span></tt></a> and <a title="HTMLParser.HTMLParser.handle_endtag" class="reference internal" href="#HTMLParser.HTMLParser.handle_endtag"><tt class="xref docutils literal"><span class="pre">handle_endtag()</span></tt></a>.</dd></dl> <dl class="method"> <dt id="HTMLParser.HTMLParser.handle_endtag"> <tt class="descclassname">HTMLParser.</tt><tt class="descname">handle_endtag</tt><big>(</big><em>tag</em><big>)</big><a class="headerlink" href="#HTMLParser.HTMLParser.handle_endtag" title="Permalink to this definition">¶</a></dt> <dd>This method is called to handle the end tag of an element. It is intended to be overridden by a derived class; the base class implementation does nothing. The <em>tag</em> argument is the name of the tag converted to lower case.</dd></dl> <dl class="method"> <dt id="HTMLParser.HTMLParser.handle_data"> <tt class="descclassname">HTMLParser.</tt><tt class="descname">handle_data</tt><big>(</big><em>data</em><big>)</big><a class="headerlink" href="#HTMLParser.HTMLParser.handle_data" title="Permalink to this definition">¶</a></dt> <dd>This method is called to process arbitrary data. It is intended to be overridden by a derived class; the base class implementation does nothing.</dd></dl> <dl class="method"> <dt id="HTMLParser.HTMLParser.handle_charref"> <tt class="descclassname">HTMLParser.</tt><tt class="descname">handle_charref</tt><big>(</big><em>name</em><big>)</big><a class="headerlink" href="#HTMLParser.HTMLParser.handle_charref" title="Permalink to this definition">¶</a></dt> <dd>This method is called to process a character reference of the form <tt class="docutils literal"><span class="pre">&#ref;</span></tt>. It is intended to be overridden by a derived class; the base class implementation does nothing.</dd></dl> <dl class="method"> <dt id="HTMLParser.HTMLParser.handle_entityref"> <tt class="descclassname">HTMLParser.</tt><tt class="descname">handle_entityref</tt><big>(</big><em>name</em><big>)</big><a class="headerlink" href="#HTMLParser.HTMLParser.handle_entityref" title="Permalink to this definition">¶</a></dt> <dd>This method is called to process a general entity reference of the form <tt class="docutils literal"><span class="pre">&name;</span></tt> where <em>name</em> is an general entity reference. It is intended to be overridden by a derived class; the base class implementation does nothing.</dd></dl> <dl class="method"> <dt id="HTMLParser.HTMLParser.handle_comment"> <tt class="descclassname">HTMLParser.</tt><tt class="descname">handle_comment</tt><big>(</big><em>data</em><big>)</big><a class="headerlink" href="#HTMLParser.HTMLParser.handle_comment" title="Permalink to this definition">¶</a></dt> <dd>This method is called when a comment is encountered. The <em>comment</em> argument is a string containing the text between the <tt class="docutils literal"><span class="pre">--</span></tt> and <tt class="docutils literal"><span class="pre">--</span></tt> delimiters, but not the delimiters themselves. For example, the comment <tt class="docutils literal"><span class="pre"><!--text--></span></tt> will cause this method to be called with the argument <tt class="docutils literal"><span class="pre">'text'</span></tt>. It is intended to be overridden by a derived class; the base class implementation does nothing.</dd></dl> <dl class="method"> <dt id="HTMLParser.HTMLParser.handle_decl"> <tt class="descclassname">HTMLParser.</tt><tt class="descname">handle_decl</tt><big>(</big><em>decl</em><big>)</big><a class="headerlink" href="#HTMLParser.HTMLParser.handle_decl" title="Permalink to this definition">¶</a></dt> <dd>Method called when an SGML <tt class="docutils literal"><span class="pre">doctype</span></tt> declaration is read by the parser. The <em>decl</em> parameter will be the entire contents of the declaration inside the <tt class="docutils literal"><span class="pre"><!...></span></tt> markup. It is intended to be overridden by a derived class; the base class implementation does nothing.</dd></dl> <dl class="method"> <dt id="HTMLParser.HTMLParser.unknown_decl"> <tt class="descclassname">HTMLParser.</tt><tt class="descname">unknown_decl</tt><big>(</big><em>data</em><big>)</big><a class="headerlink" href="#HTMLParser.HTMLParser.unknown_decl" title="Permalink to this definition">¶</a></dt> <dd>Method called when an unrecognized SGML declaration is read by the parser. The <em>data</em> parameter will be the entire contents of the declaration inside the <tt class="docutils literal"><span class="pre"><!...></span></tt> markup. It is sometimes useful to be be overridden by a derived class; the base class implementation throws an <a title="HTMLParser.HTMLParseError" class="reference internal" href="#HTMLParser.HTMLParseError"><tt class="xref docutils literal"><span class="pre">HTMLParseError</span></tt></a>.</dd></dl> <dl class="method"> <dt id="HTMLParser.HTMLParser.handle_pi"> <tt class="descclassname">HTMLParser.</tt><tt class="descname">handle_pi</tt><big>(</big><em>data</em><big>)</big><a class="headerlink" href="#HTMLParser.HTMLParser.handle_pi" title="Permalink to this definition">¶</a></dt> <dd><p>Method called when a processing instruction is encountered. The <em>data</em> parameter will contain the entire processing instruction. For example, for the processing instruction <tt class="docutils literal"><span class="pre"><?proc</span> <span class="pre">color='red'></span></tt>, this method would be called as <tt class="docutils literal"><span class="pre">handle_pi("proc</span> <span class="pre">color='red'")</span></tt>. It is intended to be overridden by a derived class; the base class implementation does nothing.</p> <div class="admonition note"> <p class="first admonition-title">Note</p> <p class="last">The <a title="HTMLParser.HTMLParser" class="reference internal" href="#HTMLParser.HTMLParser"><tt class="xref docutils literal"><span class="pre">HTMLParser</span></tt></a> class uses the SGML syntactic rules for processing instructions. An XHTML processing instruction using the trailing <tt class="docutils literal"><span class="pre">'?'</span></tt> will cause the <tt class="docutils literal"><span class="pre">'?'</span></tt> to be included in <em>data</em>.</p> </div> </dd></dl> <div class="section" id="example-html-parser-application"> <span id="htmlparser-example"></span><h2>19.1.1. Example HTML Parser Application<a class="headerlink" href="#example-html-parser-application" title="Permalink to this headline">¶</a></h2> <p>As a basic example, below is a very basic HTML parser that uses the <a title="HTMLParser.HTMLParser" class="reference internal" href="#HTMLParser.HTMLParser"><tt class="xref docutils literal"><span class="pre">HTMLParser</span></tt></a> class to print out tags as they are encountered:</p> <div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">HTMLParser</span> <span class="kn">import</span> <span class="n">HTMLParser</span> <span class="k">class</span> <span class="nc">MyHTMLParser</span><span class="p">(</span><span class="n">HTMLParser</span><span class="p">):</span> <span class="k">def</span> <span class="nf">handle_starttag</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">tag</span><span class="p">,</span> <span class="n">attrs</span><span class="p">):</span> <span class="k">print</span> <span class="s">"Encountered the beginning of a </span><span class="si">%s</span><span class="s"> tag"</span> <span class="o">%</span> <span class="n">tag</span> <span class="k">def</span> <span class="nf">handle_endtag</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">tag</span><span class="p">):</span> <span class="k">print</span> <span class="s">"Encountered the end of a </span><span class="si">%s</span><span class="s"> tag"</span> <span class="o">%</span> <span class="n">tag</span> </pre></div> </div> </div> </div> </div> </div> </div> <div class="sphinxsidebar"> <div class="sphinxsidebarwrapper"> <h3><a href="../contents.html">Table Of Contents</a></h3> <ul> <li><a class="reference external" href="#">19.1. <tt class="docutils literal"><span class="pre">HTMLParser</span></tt> — Simple HTML and XHTML parser</a><ul> <li><a class="reference external" href="#example-html-parser-application">19.1.1. Example HTML Parser Application</a></li> </ul> </li> </ul> <h4>Previous topic</h4> <p class="topless"><a href="markup.html" title="previous chapter">19. Structured Markup Processing Tools</a></p> <h4>Next topic</h4> <p class="topless"><a href="sgmllib.html" title="next chapter">19.2. <tt class="docutils literal docutils literal"><span class="pre">sgmllib</span></tt> — Simple SGML parser</a></p> <h3>This Page</h3> <ul class="this-page-menu"> <li><a href="../bugs.html">Report a Bug</a></li> <li><a href="../_sources/library/htmlparser.txt" rel="nofollow">Show Source</a></li> </ul> <div id="searchbox" style="display: none"> <h3>Quick search</h3> <form class="search" action="../search.html" method="get"> <input type="text" name="q" size="18" /> <input type="submit" value="Go" /> <input type="hidden" name="check_keywords" value="yes" /> <input type="hidden" name="area" value="default" /> </form> <p class="searchtip" style="font-size: 90%"> Enter search terms or a module, class or function name. </p> </div> <script type="text/javascript">$('#searchbox').show(0);</script> </div> </div> <div class="clearer"></div> </div> <div class="related"> <h3>Navigation</h3> <ul> <li class="right" style="margin-right: 10px"> <a href="../genindex.html" title="General Index" >index</a></li> <li class="right" > <a href="../modindex.html" title="Global Module Index" >modules</a> |</li> <li class="right" > <a href="sgmllib.html" title="19.2. sgmllib — Simple SGML parser" >next</a> |</li> <li class="right" > <a href="markup.html" title="19. 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