html.parser — Simple HTML and XHTML parser¶
This module defines a class HTMLParser which serves as the basis for parsing text files formatted in HTML (HyperText Mark-up Language) and XHTML.
class html.parser. HTMLParser ( * , convert_charrefs = True ) ¶
Create a parser instance able to parse invalid markup.
If convert_charrefs is True (the default), all character references (except the ones in script / style elements) are automatically converted to the corresponding Unicode characters.
An HTMLParser instance is fed HTML data and calls handler methods when start tags, end tags, text, comments, and other markup elements are encountered. The user should subclass HTMLParser and override its methods to implement the desired behavior.
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.
Changed in version 3.4: convert_charrefs keyword argument added.
Changed in version 3.5: The default value for argument convert_charrefs is now True .
Example HTML Parser Application¶
As a basic example, below is a simple HTML parser that uses the HTMLParser class to print out start tags, end tags, and data as they are encountered:
from html.parser import HTMLParser class MyHTMLParser(HTMLParser): def handle_starttag(self, tag, attrs): print("Encountered a start tag:", tag) def handle_endtag(self, tag): print("Encountered an end tag :", tag) def handle_data(self, data): print("Encountered some data :", data) parser = MyHTMLParser() parser.feed('' 'Parse me!
')
Encountered a start tag: html Encountered a start tag: head Encountered a start tag: title Encountered some data : Test Encountered an end tag : title Encountered an end tag : head Encountered a start tag: body Encountered a start tag: h1 Encountered some data : Parse me! Encountered an end tag : h1 Encountered an end tag : body Encountered an end tag : html
HTMLParser Methods¶
HTMLParser instances have the following methods:
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 close() is called. data must be str .
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 HTMLParser base class method close() .
Reset the instance. Loses all unprocessed data. This is called implicitly at instantiation time.
Return current line number and offset.
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.).
The following methods are called when data or markup elements are encountered and they are meant to be overridden in a subclass. The base class implementations do nothing (except for handle_startendtag() ):
HTMLParser. handle_starttag ( tag , attrs ) ¶
This method is called to handle the start tag of an element (e.g. ).
The tag argument is the name of the tag converted to lower case. The attrs argument is a list of (name, value) pairs containing the attributes found inside the tag’s <> brackets. The name will be translated to lower case, and quotes in the value have been removed, and character and entity references have been replaced.
For instance, for the tag , this method would be called as handle_starttag(‘a’, [(‘href’, ‘https://www.cwi.nl/’)]) .
All entity references from html.entities are replaced in the attribute values.
HTMLParser. handle_endtag ( tag ) ¶
This method is called to handle the end tag of an element (e.g.