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<div class="section" id="module-html.parser">
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<span id="html-parser-simple-html-and-xhtml-parser"></span><h1><a class="reference internal" href="#module-html.parser" title="html.parser: A simple parser that can handle HTML and XHTML."><code class="xref py py-mod docutils literal notranslate"><span class="pre">html.parser</span></code></a> — Simple HTML and XHTML parser<a class="headerlink" href="#module-html.parser" title="Permalink to this headline">¶</a></h1>
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<p><strong>Source code:</strong> <a class="reference external" href="https://github.com/python/cpython/tree/3.7/Lib/html/parser.py">Lib/html/parser.py</a></p>
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<hr class="docutils" id="index-0" />
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<p>This module defines a class <a class="reference internal" href="#html.parser.HTMLParser" title="html.parser.HTMLParser"><code class="xref py py-class docutils literal notranslate"><span class="pre">HTMLParser</span></code></a> which serves as the basis for
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parsing text files formatted in HTML (HyperText Mark-up Language) and XHTML.</p>
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<dl class="class">
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<dt id="html.parser.HTMLParser">
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<em class="property">class </em><code class="descclassname">html.parser.</code><code class="descname">HTMLParser</code><span class="sig-paren">(</span><em>*</em>, <em>convert_charrefs=True</em><span class="sig-paren">)</span><a class="headerlink" href="#html.parser.HTMLParser" title="Permalink to this definition">¶</a></dt>
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<dd><p>Create a parser instance able to parse invalid markup.</p>
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<p>If <em>convert_charrefs</em> is <code class="docutils literal notranslate"><span class="pre">True</span></code> (the default), all character
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references (except the ones in <code class="docutils literal notranslate"><span class="pre">script</span></code>/<code class="docutils literal notranslate"><span class="pre">style</span></code> elements) are
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automatically converted to the corresponding Unicode characters.</p>
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<p>An <a class="reference internal" href="#html.parser.HTMLParser" title="html.parser.HTMLParser"><code class="xref py py-class docutils literal notranslate"><span class="pre">HTMLParser</span></code></a> instance is fed HTML data and calls handler methods
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when start tags, end tags, text, comments, and other markup elements are
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encountered. The user should subclass <a class="reference internal" href="#html.parser.HTMLParser" title="html.parser.HTMLParser"><code class="xref py py-class docutils literal notranslate"><span class="pre">HTMLParser</span></code></a> and override its
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methods to implement the desired behavior.</p>
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<p>This parser does not check that end tags match start tags or call the end-tag
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handler for elements which are closed implicitly by closing an outer element.</p>
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<div class="versionchanged">
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<p><span class="versionmodified changed">Changed in version 3.4: </span><em>convert_charrefs</em> keyword argument added.</p>
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</div>
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<div class="versionchanged">
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<p><span class="versionmodified changed">Changed in version 3.5: </span>The default value for argument <em>convert_charrefs</em> is now <code class="docutils literal notranslate"><span class="pre">True</span></code>.</p>
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</div>
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</dd></dl>
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<div class="section" id="example-html-parser-application">
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<h2>Example HTML Parser Application<a class="headerlink" href="#example-html-parser-application" title="Permalink to this headline">¶</a></h2>
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<p>As a basic example, below is a simple HTML parser that uses the
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<a class="reference internal" href="#html.parser.HTMLParser" title="html.parser.HTMLParser"><code class="xref py py-class docutils literal notranslate"><span class="pre">HTMLParser</span></code></a> class to print out start tags, end tags, and data
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as they are encountered:</p>
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<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="kn">from</span> <span class="nn">html.parser</span> <span class="k">import</span> <span class="n">HTMLParser</span>
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<span class="k">class</span> <span class="nc">MyHTMLParser</span><span class="p">(</span><span class="n">HTMLParser</span><span class="p">):</span>
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<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>
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<span class="nb">print</span><span class="p">(</span><span class="s2">"Encountered a start tag:"</span><span class="p">,</span> <span class="n">tag</span><span class="p">)</span>
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<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>
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<span class="nb">print</span><span class="p">(</span><span class="s2">"Encountered an end tag :"</span><span class="p">,</span> <span class="n">tag</span><span class="p">)</span>
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<span class="k">def</span> <span class="nf">handle_data</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">data</span><span class="p">):</span>
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<span class="nb">print</span><span class="p">(</span><span class="s2">"Encountered some data :"</span><span class="p">,</span> <span class="n">data</span><span class="p">)</span>
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<span class="n">parser</span> <span class="o">=</span> <span class="n">MyHTMLParser</span><span class="p">()</span>
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<span class="n">parser</span><span class="o">.</span><span class="n">feed</span><span class="p">(</span><span class="s1">'<html><head><title>Test</title></head>'</span>
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<span class="s1">'<body><h1>Parse me!</h1></body></html>'</span><span class="p">)</span>
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</pre></div>
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</div>
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<p>The output will then be:</p>
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<div class="highlight-none notranslate"><div class="highlight"><pre><span></span>Encountered a start tag: html
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Encountered a start tag: head
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Encountered a start tag: title
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Encountered some data : Test
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Encountered an end tag : title
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Encountered an end tag : head
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Encountered a start tag: body
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Encountered a start tag: h1
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Encountered some data : Parse me!
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Encountered an end tag : h1
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Encountered an end tag : body
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Encountered an end tag : html
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</pre></div>
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</div>
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</div>
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<div class="section" id="htmlparser-methods">
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<h2><a class="reference internal" href="#html.parser.HTMLParser" title="html.parser.HTMLParser"><code class="xref py py-class docutils literal notranslate"><span class="pre">HTMLParser</span></code></a> Methods<a class="headerlink" href="#htmlparser-methods" title="Permalink to this headline">¶</a></h2>
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<p><a class="reference internal" href="#html.parser.HTMLParser" title="html.parser.HTMLParser"><code class="xref py py-class docutils literal notranslate"><span class="pre">HTMLParser</span></code></a> instances have the following methods:</p>
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<dl class="method">
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<dt id="html.parser.HTMLParser.feed">
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<code class="descclassname">HTMLParser.</code><code class="descname">feed</code><span class="sig-paren">(</span><em>data</em><span class="sig-paren">)</span><a class="headerlink" href="#html.parser.HTMLParser.feed" title="Permalink to this definition">¶</a></dt>
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<dd><p>Feed some text to the parser. It is processed insofar as it consists of
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complete elements; incomplete data is buffered until more data is fed or
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<a class="reference internal" href="#html.parser.HTMLParser.close" title="html.parser.HTMLParser.close"><code class="xref py py-meth docutils literal notranslate"><span class="pre">close()</span></code></a> is called. <em>data</em> must be <a class="reference internal" href="stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate"><span class="pre">str</span></code></a>.</p>
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</dd></dl>
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<dl class="method">
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<dt id="html.parser.HTMLParser.close">
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<code class="descclassname">HTMLParser.</code><code class="descname">close</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#html.parser.HTMLParser.close" title="Permalink to this definition">¶</a></dt>
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<dd><p>Force processing of all buffered data as if it were followed by an end-of-file
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mark. This method may be redefined by a derived class to define additional
|
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processing at the end of the input, but the redefined version should always call
|
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the <a class="reference internal" href="#html.parser.HTMLParser" title="html.parser.HTMLParser"><code class="xref py py-class docutils literal notranslate"><span class="pre">HTMLParser</span></code></a> base class method <a class="reference internal" href="#html.parser.HTMLParser.close" title="html.parser.HTMLParser.close"><code class="xref py py-meth docutils literal notranslate"><span class="pre">close()</span></code></a>.</p>
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</dd></dl>
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<dl class="method">
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<dt id="html.parser.HTMLParser.reset">
|
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<code class="descclassname">HTMLParser.</code><code class="descname">reset</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#html.parser.HTMLParser.reset" title="Permalink to this definition">¶</a></dt>
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<dd><p>Reset the instance. Loses all unprocessed data. This is called implicitly at
|
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instantiation time.</p>
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</dd></dl>
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<dl class="method">
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<dt id="html.parser.HTMLParser.getpos">
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<code class="descclassname">HTMLParser.</code><code class="descname">getpos</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#html.parser.HTMLParser.getpos" title="Permalink to this definition">¶</a></dt>
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<dd><p>Return current line number and offset.</p>
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</dd></dl>
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<dl class="method">
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<dt id="html.parser.HTMLParser.get_starttag_text">
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<code class="descclassname">HTMLParser.</code><code class="descname">get_starttag_text</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#html.parser.HTMLParser.get_starttag_text" title="Permalink to this definition">¶</a></dt>
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<dd><p>Return the text of the most recently opened start tag. This should not normally
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be needed for structured processing, but may be useful in dealing with HTML “as
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deployed” or for re-generating input with minimal changes (whitespace between
|
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attributes can be preserved, etc.).</p>
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</dd></dl>
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<p>The following methods are called when data or markup elements are encountered
|
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and they are meant to be overridden in a subclass. The base class
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implementations do nothing (except for <a class="reference internal" href="#html.parser.HTMLParser.handle_startendtag" title="html.parser.HTMLParser.handle_startendtag"><code class="xref py py-meth docutils literal notranslate"><span class="pre">handle_startendtag()</span></code></a>):</p>
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<dl class="method">
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<dt id="html.parser.HTMLParser.handle_starttag">
|
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<code class="descclassname">HTMLParser.</code><code class="descname">handle_starttag</code><span class="sig-paren">(</span><em>tag</em>, <em>attrs</em><span class="sig-paren">)</span><a class="headerlink" href="#html.parser.HTMLParser.handle_starttag" title="Permalink to this definition">¶</a></dt>
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<dd><p>This method is called to handle the start of a tag (e.g. <code class="docutils literal notranslate"><span class="pre"><div</span> <span class="pre">id="main"></span></code>).</p>
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<p>The <em>tag</em> argument is the name of the tag converted to lower case. The <em>attrs</em>
|
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argument is a list of <code class="docutils literal notranslate"><span class="pre">(name,</span> <span class="pre">value)</span></code> pairs containing the attributes found
|
||
inside the tag’s <code class="docutils literal notranslate"><span class="pre"><></span></code> 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.</p>
|
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<p>For instance, for the tag <code class="docutils literal notranslate"><span class="pre"><A</span> <span class="pre">HREF="https://www.cwi.nl/"></span></code>, this method
|
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would be called as <code class="docutils literal notranslate"><span class="pre">handle_starttag('a',</span> <span class="pre">[('href',</span> <span class="pre">'https://www.cwi.nl/')])</span></code>.</p>
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<p>All entity references from <a class="reference internal" href="html.entities.html#module-html.entities" title="html.entities: Definitions of HTML general entities."><code class="xref py py-mod docutils literal notranslate"><span class="pre">html.entities</span></code></a> are replaced in the attribute
|
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values.</p>
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</dd></dl>
|
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|
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<dl class="method">
|
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<dt id="html.parser.HTMLParser.handle_endtag">
|
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<code class="descclassname">HTMLParser.</code><code class="descname">handle_endtag</code><span class="sig-paren">(</span><em>tag</em><span class="sig-paren">)</span><a class="headerlink" href="#html.parser.HTMLParser.handle_endtag" title="Permalink to this definition">¶</a></dt>
|
||
<dd><p>This method is called to handle the end tag of an element (e.g. <code class="docutils literal notranslate"><span class="pre"></div></span></code>).</p>
|
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<p>The <em>tag</em> argument is the name of the tag converted to lower case.</p>
|
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</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="html.parser.HTMLParser.handle_startendtag">
|
||
<code class="descclassname">HTMLParser.</code><code class="descname">handle_startendtag</code><span class="sig-paren">(</span><em>tag</em>, <em>attrs</em><span class="sig-paren">)</span><a class="headerlink" href="#html.parser.HTMLParser.handle_startendtag" title="Permalink to this definition">¶</a></dt>
|
||
<dd><p>Similar to <a class="reference internal" href="#html.parser.HTMLParser.handle_starttag" title="html.parser.HTMLParser.handle_starttag"><code class="xref py py-meth docutils literal notranslate"><span class="pre">handle_starttag()</span></code></a>, but called when the parser encounters an
|
||
XHTML-style empty tag (<code class="docutils literal notranslate"><span class="pre"><img</span> <span class="pre">...</span> <span class="pre">/></span></code>). This method may be overridden by
|
||
subclasses which require this particular lexical information; the default
|
||
implementation simply calls <a class="reference internal" href="#html.parser.HTMLParser.handle_starttag" title="html.parser.HTMLParser.handle_starttag"><code class="xref py py-meth docutils literal notranslate"><span class="pre">handle_starttag()</span></code></a> and <a class="reference internal" href="#html.parser.HTMLParser.handle_endtag" title="html.parser.HTMLParser.handle_endtag"><code class="xref py py-meth docutils literal notranslate"><span class="pre">handle_endtag()</span></code></a>.</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="html.parser.HTMLParser.handle_data">
|
||
<code class="descclassname">HTMLParser.</code><code class="descname">handle_data</code><span class="sig-paren">(</span><em>data</em><span class="sig-paren">)</span><a class="headerlink" href="#html.parser.HTMLParser.handle_data" title="Permalink to this definition">¶</a></dt>
|
||
<dd><p>This method is called to process arbitrary data (e.g. text nodes and the
|
||
content of <code class="docutils literal notranslate"><span class="pre"><script>...</script></span></code> and <code class="docutils literal notranslate"><span class="pre"><style>...</style></span></code>).</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="html.parser.HTMLParser.handle_entityref">
|
||
<code class="descclassname">HTMLParser.</code><code class="descname">handle_entityref</code><span class="sig-paren">(</span><em>name</em><span class="sig-paren">)</span><a class="headerlink" href="#html.parser.HTMLParser.handle_entityref" title="Permalink to this definition">¶</a></dt>
|
||
<dd><p>This method is called to process a named character reference of the form
|
||
<code class="docutils literal notranslate"><span class="pre">&name;</span></code> (e.g. <code class="docutils literal notranslate"><span class="pre">&gt;</span></code>), where <em>name</em> is a general entity reference
|
||
(e.g. <code class="docutils literal notranslate"><span class="pre">'gt'</span></code>). This method is never called if <em>convert_charrefs</em> is
|
||
<code class="docutils literal notranslate"><span class="pre">True</span></code>.</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="html.parser.HTMLParser.handle_charref">
|
||
<code class="descclassname">HTMLParser.</code><code class="descname">handle_charref</code><span class="sig-paren">(</span><em>name</em><span class="sig-paren">)</span><a class="headerlink" href="#html.parser.HTMLParser.handle_charref" title="Permalink to this definition">¶</a></dt>
|
||
<dd><p>This method is called to process decimal and hexadecimal numeric character
|
||
references of the form <code class="docutils literal notranslate"><span class="pre">&#NNN;</span></code> and <code class="docutils literal notranslate"><span class="pre">&#xNNN;</span></code>. For example, the decimal
|
||
equivalent for <code class="docutils literal notranslate"><span class="pre">&gt;</span></code> is <code class="docutils literal notranslate"><span class="pre">&#62;</span></code>, whereas the hexadecimal is <code class="docutils literal notranslate"><span class="pre">&#x3E;</span></code>;
|
||
in this case the method will receive <code class="docutils literal notranslate"><span class="pre">'62'</span></code> or <code class="docutils literal notranslate"><span class="pre">'x3E'</span></code>. This method
|
||
is never called if <em>convert_charrefs</em> is <code class="docutils literal notranslate"><span class="pre">True</span></code>.</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="html.parser.HTMLParser.handle_comment">
|
||
<code class="descclassname">HTMLParser.</code><code class="descname">handle_comment</code><span class="sig-paren">(</span><em>data</em><span class="sig-paren">)</span><a class="headerlink" href="#html.parser.HTMLParser.handle_comment" title="Permalink to this definition">¶</a></dt>
|
||
<dd><p>This method is called when a comment is encountered (e.g. <code class="docutils literal notranslate"><span class="pre"><!--comment--></span></code>).</p>
|
||
<p>For example, the comment <code class="docutils literal notranslate"><span class="pre"><!--</span> <span class="pre">comment</span> <span class="pre">--></span></code> will cause this method to be
|
||
called with the argument <code class="docutils literal notranslate"><span class="pre">'</span> <span class="pre">comment</span> <span class="pre">'</span></code>.</p>
|
||
<p>The content of Internet Explorer conditional comments (condcoms) will also be
|
||
sent to this method, so, for <code class="docutils literal notranslate"><span class="pre"><!--[if</span> <span class="pre">IE</span> <span class="pre">9]>IE9-specific</span> <span class="pre">content<![endif]--></span></code>,
|
||
this method will receive <code class="docutils literal notranslate"><span class="pre">'[if</span> <span class="pre">IE</span> <span class="pre">9]>IE9-specific</span> <span class="pre">content<![endif]'</span></code>.</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="html.parser.HTMLParser.handle_decl">
|
||
<code class="descclassname">HTMLParser.</code><code class="descname">handle_decl</code><span class="sig-paren">(</span><em>decl</em><span class="sig-paren">)</span><a class="headerlink" href="#html.parser.HTMLParser.handle_decl" title="Permalink to this definition">¶</a></dt>
|
||
<dd><p>This method is called to handle an HTML doctype declaration (e.g.
|
||
<code class="docutils literal notranslate"><span class="pre"><!DOCTYPE</span> <span class="pre">html></span></code>).</p>
|
||
<p>The <em>decl</em> parameter will be the entire contents of the declaration inside
|
||
the <code class="docutils literal notranslate"><span class="pre"><!...></span></code> markup (e.g. <code class="docutils literal notranslate"><span class="pre">'DOCTYPE</span> <span class="pre">html'</span></code>).</p>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="html.parser.HTMLParser.handle_pi">
|
||
<code class="descclassname">HTMLParser.</code><code class="descname">handle_pi</code><span class="sig-paren">(</span><em>data</em><span class="sig-paren">)</span><a class="headerlink" href="#html.parser.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 <code class="docutils literal notranslate"><span class="pre"><?proc</span> <span class="pre">color='red'></span></code>, this method would be called as
|
||
<code class="docutils literal notranslate"><span class="pre">handle_pi("proc</span> <span class="pre">color='red'")</span></code>. It is intended to be overridden by a derived
|
||
class; the base class implementation does nothing.</p>
|
||
<div class="admonition note">
|
||
<p class="admonition-title">Note</p>
|
||
<p>The <a class="reference internal" href="#html.parser.HTMLParser" title="html.parser.HTMLParser"><code class="xref py py-class docutils literal notranslate"><span class="pre">HTMLParser</span></code></a> class uses the SGML syntactic rules for processing
|
||
instructions. An XHTML processing instruction using the trailing <code class="docutils literal notranslate"><span class="pre">'?'</span></code> will
|
||
cause the <code class="docutils literal notranslate"><span class="pre">'?'</span></code> to be included in <em>data</em>.</p>
|
||
</div>
|
||
</dd></dl>
|
||
|
||
<dl class="method">
|
||
<dt id="html.parser.HTMLParser.unknown_decl">
|
||
<code class="descclassname">HTMLParser.</code><code class="descname">unknown_decl</code><span class="sig-paren">(</span><em>data</em><span class="sig-paren">)</span><a class="headerlink" href="#html.parser.HTMLParser.unknown_decl" title="Permalink to this definition">¶</a></dt>
|
||
<dd><p>This method is called when an unrecognized declaration is read by the parser.</p>
|
||
<p>The <em>data</em> parameter will be the entire contents of the declaration inside
|
||
the <code class="docutils literal notranslate"><span class="pre"><![...]></span></code> markup. It is sometimes useful to be overridden by a
|
||
derived class. The base class implementation does nothing.</p>
|
||
</dd></dl>
|
||
|
||
</div>
|
||
<div class="section" id="examples">
|
||
<span id="htmlparser-examples"></span><h2>Examples<a class="headerlink" href="#examples" title="Permalink to this headline">¶</a></h2>
|
||
<p>The following class implements a parser that will be used to illustrate more
|
||
examples:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="kn">from</span> <span class="nn">html.parser</span> <span class="k">import</span> <span class="n">HTMLParser</span>
|
||
<span class="kn">from</span> <span class="nn">html.entities</span> <span class="k">import</span> <span class="n">name2codepoint</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="nb">print</span><span class="p">(</span><span class="s2">"Start tag:"</span><span class="p">,</span> <span class="n">tag</span><span class="p">)</span>
|
||
<span class="k">for</span> <span class="n">attr</span> <span class="ow">in</span> <span class="n">attrs</span><span class="p">:</span>
|
||
<span class="nb">print</span><span class="p">(</span><span class="s2">" attr:"</span><span class="p">,</span> <span class="n">attr</span><span class="p">)</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="nb">print</span><span class="p">(</span><span class="s2">"End tag :"</span><span class="p">,</span> <span class="n">tag</span><span class="p">)</span>
|
||
|
||
<span class="k">def</span> <span class="nf">handle_data</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">data</span><span class="p">):</span>
|
||
<span class="nb">print</span><span class="p">(</span><span class="s2">"Data :"</span><span class="p">,</span> <span class="n">data</span><span class="p">)</span>
|
||
|
||
<span class="k">def</span> <span class="nf">handle_comment</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">data</span><span class="p">):</span>
|
||
<span class="nb">print</span><span class="p">(</span><span class="s2">"Comment :"</span><span class="p">,</span> <span class="n">data</span><span class="p">)</span>
|
||
|
||
<span class="k">def</span> <span class="nf">handle_entityref</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">name</span><span class="p">):</span>
|
||
<span class="n">c</span> <span class="o">=</span> <span class="nb">chr</span><span class="p">(</span><span class="n">name2codepoint</span><span class="p">[</span><span class="n">name</span><span class="p">])</span>
|
||
<span class="nb">print</span><span class="p">(</span><span class="s2">"Named ent:"</span><span class="p">,</span> <span class="n">c</span><span class="p">)</span>
|
||
|
||
<span class="k">def</span> <span class="nf">handle_charref</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">name</span><span class="p">):</span>
|
||
<span class="k">if</span> <span class="n">name</span><span class="o">.</span><span class="n">startswith</span><span class="p">(</span><span class="s1">'x'</span><span class="p">):</span>
|
||
<span class="n">c</span> <span class="o">=</span> <span class="nb">chr</span><span class="p">(</span><span class="nb">int</span><span class="p">(</span><span class="n">name</span><span class="p">[</span><span class="mi">1</span><span class="p">:],</span> <span class="mi">16</span><span class="p">))</span>
|
||
<span class="k">else</span><span class="p">:</span>
|
||
<span class="n">c</span> <span class="o">=</span> <span class="nb">chr</span><span class="p">(</span><span class="nb">int</span><span class="p">(</span><span class="n">name</span><span class="p">))</span>
|
||
<span class="nb">print</span><span class="p">(</span><span class="s2">"Num ent :"</span><span class="p">,</span> <span class="n">c</span><span class="p">)</span>
|
||
|
||
<span class="k">def</span> <span class="nf">handle_decl</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">data</span><span class="p">):</span>
|
||
<span class="nb">print</span><span class="p">(</span><span class="s2">"Decl :"</span><span class="p">,</span> <span class="n">data</span><span class="p">)</span>
|
||
|
||
<span class="n">parser</span> <span class="o">=</span> <span class="n">MyHTMLParser</span><span class="p">()</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>Parsing a doctype:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="n">parser</span><span class="o">.</span><span class="n">feed</span><span class="p">(</span><span class="s1">'<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" '</span>
|
||
<span class="gp">... </span> <span class="s1">'"http://www.w3.org/TR/html4/strict.dtd">'</span><span class="p">)</span>
|
||
<span class="go">Decl : DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>Parsing an element with a few attributes and a title:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="n">parser</span><span class="o">.</span><span class="n">feed</span><span class="p">(</span><span class="s1">'<img src="python-logo.png" alt="The Python logo">'</span><span class="p">)</span>
|
||
<span class="go">Start tag: img</span>
|
||
<span class="go"> attr: ('src', 'python-logo.png')</span>
|
||
<span class="go"> attr: ('alt', 'The Python logo')</span>
|
||
<span class="go">>>></span>
|
||
<span class="gp">>>> </span><span class="n">parser</span><span class="o">.</span><span class="n">feed</span><span class="p">(</span><span class="s1">'<h1>Python</h1>'</span><span class="p">)</span>
|
||
<span class="go">Start tag: h1</span>
|
||
<span class="go">Data : Python</span>
|
||
<span class="go">End tag : h1</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>The content of <code class="docutils literal notranslate"><span class="pre">script</span></code> and <code class="docutils literal notranslate"><span class="pre">style</span></code> elements is returned as is, without
|
||
further parsing:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="n">parser</span><span class="o">.</span><span class="n">feed</span><span class="p">(</span><span class="s1">'<style type="text/css">#python { color: green }</style>'</span><span class="p">)</span>
|
||
<span class="go">Start tag: style</span>
|
||
<span class="go"> attr: ('type', 'text/css')</span>
|
||
<span class="go">Data : #python { color: green }</span>
|
||
<span class="go">End tag : style</span>
|
||
|
||
<span class="gp">>>> </span><span class="n">parser</span><span class="o">.</span><span class="n">feed</span><span class="p">(</span><span class="s1">'<script type="text/javascript">'</span>
|
||
<span class="gp">... </span> <span class="s1">'alert("<strong>hello!</strong>");</script>'</span><span class="p">)</span>
|
||
<span class="go">Start tag: script</span>
|
||
<span class="go"> attr: ('type', 'text/javascript')</span>
|
||
<span class="go">Data : alert("<strong>hello!</strong>");</span>
|
||
<span class="go">End tag : script</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>Parsing comments:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="n">parser</span><span class="o">.</span><span class="n">feed</span><span class="p">(</span><span class="s1">'<!-- a comment -->'</span>
|
||
<span class="gp">... </span> <span class="s1">'<!--[if IE 9]>IE-specific content<![endif]-->'</span><span class="p">)</span>
|
||
<span class="go">Comment : a comment</span>
|
||
<span class="go">Comment : [if IE 9]>IE-specific content<![endif]</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>Parsing named and numeric character references and converting them to the
|
||
correct char (note: these 3 references are all equivalent to <code class="docutils literal notranslate"><span class="pre">'>'</span></code>):</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="n">parser</span><span class="o">.</span><span class="n">feed</span><span class="p">(</span><span class="s1">'&gt;&#62;&#x3E;'</span><span class="p">)</span>
|
||
<span class="go">Named ent: ></span>
|
||
<span class="go">Num ent : ></span>
|
||
<span class="go">Num ent : ></span>
|
||
</pre></div>
|
||
</div>
|
||
<p>Feeding incomplete chunks to <a class="reference internal" href="#html.parser.HTMLParser.feed" title="html.parser.HTMLParser.feed"><code class="xref py py-meth docutils literal notranslate"><span class="pre">feed()</span></code></a> works, but
|
||
<a class="reference internal" href="#html.parser.HTMLParser.handle_data" title="html.parser.HTMLParser.handle_data"><code class="xref py py-meth docutils literal notranslate"><span class="pre">handle_data()</span></code></a> might be called more than once
|
||
(unless <em>convert_charrefs</em> is set to <code class="docutils literal notranslate"><span class="pre">True</span></code>):</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="k">for</span> <span class="n">chunk</span> <span class="ow">in</span> <span class="p">[</span><span class="s1">'<sp'</span><span class="p">,</span> <span class="s1">'an>buff'</span><span class="p">,</span> <span class="s1">'ered '</span><span class="p">,</span> <span class="s1">'text</s'</span><span class="p">,</span> <span class="s1">'pan>'</span><span class="p">]:</span>
|
||
<span class="gp">... </span> <span class="n">parser</span><span class="o">.</span><span class="n">feed</span><span class="p">(</span><span class="n">chunk</span><span class="p">)</span>
|
||
<span class="gp">...</span>
|
||
<span class="go">Start tag: span</span>
|
||
<span class="go">Data : buff</span>
|
||
<span class="go">Data : ered</span>
|
||
<span class="go">Data : text</span>
|
||
<span class="go">End tag : span</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>Parsing invalid HTML (e.g. unquoted attributes) also works:</p>
|
||
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="n">parser</span><span class="o">.</span><span class="n">feed</span><span class="p">(</span><span class="s1">'<p><a class=link href=#main>tag soup</p ></a>'</span><span class="p">)</span>
|
||
<span class="go">Start tag: p</span>
|
||
<span class="go">Start tag: a</span>
|
||
<span class="go"> attr: ('class', 'link')</span>
|
||
<span class="go"> attr: ('href', '#main')</span>
|
||
<span class="go">Data : tag soup</span>
|
||
<span class="go">End tag : p</span>
|
||
<span class="go">End tag : a</span>
|
||
</pre></div>
|
||
</div>
|
||
</div>
|
||
</div>
|
||
|
||
|
||
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|
||
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|
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<div class="sphinxsidebar" role="navigation" aria-label="main navigation">
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|
||
<h3><a href="../contents.html">Table of Contents</a></h3>
|
||
<ul>
|
||
<li><a class="reference internal" href="#"><code class="xref py py-mod docutils literal notranslate"><span class="pre">html.parser</span></code> — Simple HTML and XHTML parser</a><ul>
|
||
<li><a class="reference internal" href="#example-html-parser-application">Example HTML Parser Application</a></li>
|
||
<li><a class="reference internal" href="#htmlparser-methods"><code class="xref py py-class docutils literal notranslate"><span class="pre">HTMLParser</span></code> Methods</a></li>
|
||
<li><a class="reference internal" href="#examples">Examples</a></li>
|
||
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|
||
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|
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|
||
<p class="topless"><a href="html.html"
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||
title="previous chapter"><code class="xref py py-mod docutils literal notranslate"><span class="pre">html</span></code> — HyperText Markup Language support</a></p>
|
||
<h4>Next topic</h4>
|
||
<p class="topless"><a href="html.entities.html"
|
||
title="next chapter"><code class="xref py py-mod docutils literal notranslate"><span class="pre">html.entities</span></code> — Definitions of HTML general entities</a></p>
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