Htmlparser Python

html.parser — Simple HTML and XHTML parser … – Python Docs

Source code: Lib/html/
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 (*, 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 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()

Parse me!

The output will then be:
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 of a tag (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 ‘)
Parsing an element with a few attributes and a title:
>>> (‘The Python logo‘)
Start tag: img
attr: (‘src’, ”)
attr: (‘alt’, ‘The Python logo’)
>>> (‘


Start tag: h1
Data: Python
End tag: h1
The content of script and style elements is returned as is, without
further parsing:
>>> (‘

Start tag: style
attr: (‘type’, ‘text/css’)
Data: #python { color: green}
End tag: style
>>> (‘‘)
Start tag: script
attr: (‘type’, ‘text/javascript’)
Data: alert(“hello! “);
End tag: script
Parsing comments:
>>> (‘‘… ‘IE-specific content‘)
Comment: a comment
Comment: [if IE 9]>IE-specific content‘):
>>> (‘>>>’)
Named ent: >
Num ent: >
Feeding incomplete chunks to feed() works, but
handle_data() might be called more than once
(unless convert_charrefs is set to True):
>>> for chunk in [‘buff’, ‘ered ‘, ‘text‘]:… (chunk)…
Start tag: span
Data: buff
Data: ered
Data: text
End tag: span
Parsing invalid HTML (e. unquoted attributes) also works:
>>> (‘

tag soup

Start tag: p
Start tag: a
attr: (‘class’, ‘link’)
attr: (‘href’, ‘#main’)
Data: tag soup
End tag: p
End tag: a
HTMLParser in Python 3.x - AskPython

HTMLParser in Python 3.x – AskPython

provides a very simple and efficient way for coders to read through HTML code. This library comes pre-installed in the stdlib. This simplifies our interfacing with the HTMLParser library as we do not need to install additional packages from the Python Package Index (PyPI) for the same is HTMLParser? Essentially, HTMLParser lets us understand HTML code in a nested fashion. The module has methods that are automatically called when specific HTML elements are met with. It simplifies HTML tags and data fed with HTML data, the tag reads through it one tag at a time, going from start tags to the tags within, then the end tags and so to Use HTMLParser? HTMLParser only identifies the tags or data for us but does not output any data when something is identified. We need to add functionality to the methods before they can output the information they if we need to add functionality, what’s the use of the HTMLParser? This module saves us the time of creating the functionality of identifying tags ’re not going to code how to identify the tags, only what to do once they’re identified. Understood? Great! Now let’s get into creating a parser for ourselves! Subclassing the HTMLParserHow can we add functionality to the HTMLParser methods? By subclassing. Also identified as Inheritance, we create a class that retains the behavior of HTMLParser, while adding more bclassing lets us override the default functionality of a method (which in our case, is to return nothing when tags are identified) and add some better functions instead. Let’s see how to work with the HTMLParser nding Names of The Called MethodsThere are many methods available within the module. We’ll go over the ones you’d need frequently and then learn how to make use of MLParser. handle_starttag(tag, attrs) – Called when start tags are found (example , , )HTMLParser. handle_endtag(tag) – Called when end tags are found (example , , )HTMLParser. handle_data(data) – Called when data is found (example data )HTMLParser. handle_comment(data) – Called when comments are found (example )HTMLParser. handle_decl(decl) – Called when declarations are found (example )Creating Your HTMLParserLet’s define basic print functionalities to the methods in the HTMLParser module. In the below example, all I’m doing is adding a print method whenever the method is last line in the code is where we feed data to the parser. I fed basic HTML code directly, but you can do the same by using the urllib module to directly import a website into python import HTMLParser
class Parse(HTMLParser):
def __init__(self):
#Since Python 3, we need to call the __init__() function
#of the parent class
super(). __init__()
#Defining what the methods should output when called by HTMLParser.
def handle_starttag(self, tag, attrs):
print(“Start tag: “, tag)
for a in attrs:
print(“Attributes of the tag: “, a)
def handle_data(self, data):
print(“Here’s the data: “, data)
def handle_endtag(self, tag):
print(“End tag: “, tag)
testParser = Parse()
(“Testing Parser“)
HTMLParser OutputWhat Can HTMLParser Be Used For? Web data is what most people would need the HTMLParser module for. Not to say that it cannot be used for anything else, but when you need to read loads of websites and find specific information, this module will make the task a cakewalk for MLParser Real World ExampleI’m going to pull every single link from the Python Wikipedia page for this it manually, by right-clicking on a link, copying and pasting it in a word file, and then moving on to the next is possible too. But that would take hours if there are lots of links on the page which is a typical situation with Wikipedia we’ll be spending 5 minutes to code an HTMLParser and get the time needed to finish the task from hours to a few seconds. Let’s do it! from import HTMLParser
import quest
#Import HTML from a URL
url = quest. urlopen(“(programming_language)”)
html = ()()
#Since Python 3, we need to call the __init__() function of the parent class
#Defining what the method should output when called by HTMLParser.
# Only parse the ‘anchor’ tag.
if tag == “a”:
for name, link in attrs:
if name == “href” and artswith(“”):
print (link)
p = Parse()
Python HTMLParser Web ScaperThe Python programming page on Wikipedia has more than 300 links. I’m sure it would have taken me at least an hour to make sure we had all of them. But with this simple script, it took <5 seconds to output every single link without missing any of them! ConclusionThis module is really fun to play around with. We ended up scraping tons of data from the web using this simple module in the process of writing this there are other modules like BeautifulSoup which are more well known. But for quick and simple tasks, HTMLParser does a really amazing job! What is the HTML parser in Python? -

What is the HTML parser in Python? –

from import HTMLParser
class Parser(HTMLParser):
# method to append the start tag to the list start_tags.
def handle_starttag(self, tag, attrs):
global start_tags
# method to append the end tag to the list end_tags.
def handle_endtag(self, tag):
global end_tags
# method to append the data between the tags to the list all_data.
def handle_data(self, data):
global all_data
# method to append the comment to the list comments.
def handle_comment(self, data):
global comments
start_tags = []
end_tags = []
all_data = []
comments = []
# Creating an instance of our class.
parser = Parser()
# Poviding the input.

‘I am a fan of frozen yoghurt.

<' '/body>‘)
print(“start tags:”, start_tags)
print(“end tags:”, end_tags)
print(“data:”, all_data)
print(“comments”, comments)

Frequently Asked Questions about htmlparser python

What is HTMLParser in Python?

The HTML parser is a structured markup processing tool. It defines a class called HTMLParser, ​which is used to parse HTML files. It comes in handy for web crawling​.

How do you parse an HTML body in Python?

How to parse HTML in Pythonprint(html)parsed_html = bs4. BeautifulSoup(html)body_text = parsed_html. find(“body”). text. finding the text of first body tag.print(body_text)

How do you import HTML into Python?

Use codecs. open() to open an HTML file within Python open(filename, mode, encoding) with filename as the name of the HTML file, mode as “r” , and encoding as “utf-8” to open an HTML file in read-only mode.

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