将 HTML 实体转换为 Unicode，反之亦然

Question

How do you convert HTML entities to Unicode and vice versa in Python?

Answer 1

As to the "vice versa" (which I needed myself, leading me to find this question, which didn't help, and subsequently another site which had the answer ):

u'some string'.encode('ascii', 'xmlcharrefreplace')

will return a plain string with any non-ascii characters turned into XML (HTML) entities.

Answer 2

You need to have BeautifulSoup .

from BeautifulSoup import BeautifulStoneSoup
import cgi

def HTMLEntitiesToUnicode(text):
    """Converts HTML entities to unicode.  For example '&' becomes '&'."""
    text = unicode(BeautifulStoneSoup(text, convertEntities=BeautifulStoneSoup.ALL_ENTITIES))
    return text

def unicodeToHTMLEntities(text):
    """Converts unicode to HTML entities.  For example '&' becomes '&'."""
    text = cgi.escape(text).encode('ascii', 'xmlcharrefreplace')
    return text

text = "&, ®, <, >, ¢, £, ¥, €, §, ©"

uni = HTMLEntitiesToUnicode(text)
htmlent = unicodeToHTMLEntities(uni)

print uni
print htmlent
# &, ®, <, >, ¢, £, ¥, €, §, ©
# &amp;, &#174;, &lt;, &gt;, &#162;, &#163;, &#165;, &#8364;, &#167;, &#169;

Answer 3

Update for Python 2.7 and BeautifulSoup4

Unescape -- Unicode HTML to unicode with htmlparser (Python 2.7 standard lib):

>>> escaped = u'Monsieur le Curé of the «Notre-Dame-de-Grâce» neighborhood'
>>> from HTMLParser import HTMLParser
>>> htmlparser = HTMLParser()
>>> unescaped = htmlparser.unescape(escaped)
>>> unescaped
u'Monsieur le Cur\xe9 of the \xabNotre-Dame-de-Gr\xe2ce\xbb neighborhood'
>>> print unescaped
Monsieur le Curé of the «Notre-Dame-de-Grâce» neighborhood

Unescape -- Unicode HTML to unicode with bs4 (BeautifulSoup4):

>>> html = '''<p>Monsieur le Cur&eacute; of the &laquo;Notre-Dame-de-Gr&acirc;ce&raquo; neighborhood</p>'''
>>> from bs4 import BeautifulSoup
>>> soup = BeautifulSoup(html)
>>> soup.text
u'Monsieur le Cur\xe9 of the \xabNotre-Dame-de-Gr\xe2ce\xbb neighborhood'
>>> print soup.text
Monsieur le Curé of the «Notre-Dame-de-Grâce» neighborhood

Escape -- Unicode to unicode HTML with bs4 (BeautifulSoup4):

>>> unescaped = u'Monsieur le Curé of the «Notre-Dame-de-Grâce» neighborhood'
>>> from bs4.dammit import EntitySubstitution
>>> escaper = EntitySubstitution()
>>> escaped = escaper.substitute_html(unescaped)
>>> escaped
u'Monsieur le Curé of the «Notre-Dame-de-Grâce» neighborhood'

Answer 4

As hekevintran answer suggests, you may use cgi.escape(s) for encoding stings, but notice that encoding of quote is false by default in that function and it may be a good idea to pass the quote=True keyword argument alongside your string. But even by passing quote=True , the function won't escape single quotes ( "'" ) (Because of these issues the function has been deprecated since version 3.2)

It's been suggested to use html.escape(s) instead of cgi.escape(s) . (New in version 3.2)

Also html.unescape(s) has been introduced in version 3.4 .

So in python 3.4 you can:

• Use html.escape(text).encode('ascii', 'xmlcharrefreplace').decode() to convert special characters to HTML entities.
• And html.unescape(text) for converting HTML entities back to plain-text representations.

Answer 5

$ python3 -c "
> import html
> print(
>     html.unescape('&©—')
> )"
&©—

$ python3 -c "
> import html
> print(
>     html.escape('&©—')
> )"
&©—

$ python2 -c "
> from HTMLParser import HTMLParser
> print(
>     HTMLParser().unescape('&©—')
> )"
&©—

$ python2 -c "
> import cgi
> print(
>     cgi.escape('&©—')
> )"
&©—

HTML only strictly requires & (ampersand) and < (left angle bracket / less-than sign) to be escaped. https://html.spec.whatwg.org/multipage/parsing.html#data-state

Answer 6

For python3 use html.unescape() :

import html
s = "&"
decoded = html.unescape(s)
# &

Answer 7

If someone like me is out there wondering why some entity numbers (codes) like ™ (for trademark symbol), € (for euro symbol) ™ (for trademark symbol), € (for euro symbol) ™ (for trademark symbol), € (for euro symbol) are not encoded properly, the reason is in ISO-8859-1 (aka Windows-1252) those characters are not defined.

Also note that, the default character set as of html5 is utf-8 it was ISO-8859-1 for html4

So, we will have to workaround somehow (find & replace those at first)

Reference (starting point) from Mozilla's documentation

https://developer.mozilla.org/en-US/docs/Web/Guide/Localizations_and_character_encodings

Answer 8

I used the following function to convert unicode ripped from an xls file into a an html file while conserving the special characters found in the xls file:

def html_wr(f, dat):
    ''' write dat to file f as html
        . file is assumed to be opened in binary format
        . if dat is nul it is replaced with non breakable space
        . non-ascii characters are translated to xml       
    '''
    if not dat:
        dat = ' '
    try:
        f.write(dat.encode('ascii'))
    except:
        f.write(html.escape(dat).encode('ascii', 'xmlcharrefreplace'))

hope this is useful to somebody

Answer 9

#!/usr/bin/env python3
import fileinput
import html

for line in fileinput.input():
    print(html.unescape(line.rstrip('\n')))