Equivalent to InnerHTML when using lxml.html to parse HTML

问题

I'm working on a script using lxml.html to parse web pages. I have done a fair bit of BeautifulSoup in my time but am now experimenting with lxml due to its speed.

I would like to know what the most sensible way in the library is to do the equivalent of Javascript's InnerHtml - that is, to retrieve or set the complete contents of a tag.

<body>
<h1>A title</h1>
<p>Some text</p>
</body>

InnerHtml is therefore:

<h1>A title</h1>
<p>Some text</p>

I can do it using hacks (converting to string/regexes etc) but I'm assuming that there is a correct way to do this using the library which I am missing due to unfamiliarity. Thanks for any help.

EDIT: Thanks to pobk for showing me the way on this so quickly and effectively. For anyone trying the same, here is what I ended up with:

from lxml import html
from cStringIO import StringIO
t = html.parse(StringIO(
"""<body>
<h1>A title</h1>
<p>Some text</p>
Untagged text
<p>
Unclosed p tag
</body>"""))
root = t.getroot()
body = root.body
print (element.text or '') + ''.join([html.tostring(child) for child in body.iterdescendants()])

Note that the lxml.html parser will fix up the unclosed tag, so beware if this is a problem.

回答1:

You can get the children of an ElementTree node using the getchildren() or iterdescendants() methods of the root node:

>>> from lxml import etree
>>> from cStringIO import StringIO
>>> t = etree.parse(StringIO("""<body>
... <h1>A title</h1>
... <p>Some text</p>
... </body>"""))
>>> root = t.getroot()
>>> for child in root.iterdescendants(),:
...  print etree.tostring(child)
...
<h1>A title</h1>

<p>Some text</p>

This can be shorthanded as follows:

print ''.join([etree.tostring(child) for child in root.iterdescendants()])

回答2:

Sorry for bringing this up again, but I've been looking for a solution and yours contains a bug:

<body>This text is ignored
<h1>Title</h1><p>Some text</p></body>

Text directly under the root element is ignored. I ended up doing this:

(body.text or '') +\
''.join([html.tostring(child) for child in body.iterchildren()])

回答3:

import lxml.etree as ET

     body = t.xpath("//body");
     for tag in body:
         h = html.fromstring( ET.tostring(tag[0]) ).xpath("//h1");
         p = html.fromstring(  ET.tostring(tag[1]) ).xpath("//p");             
         htext = h[0].text_content();
         ptext = h[0].text_content();

you can also use .get('href') for a tag and .attrib for attribute ,

here tag no is hardcoded but you can also do this dynamic

回答4:

Here is a Python 3 version:

from xml.sax import saxutils
from lxml import html

def inner_html(tree):
    """ Return inner HTML of lxml element """
    return (saxutils.escape(tree.text) if tree.text else '') + \
        ''.join([html.tostring(child, encoding=str) for child in tree.iterchildren()])

Note that this includes escaping of the initial text as recommended by andreymal -- this is needed to avoid tag injection if you're working with sanitized HTML!

来源：https://stackoverflow.com/questions/6123351/equivalent-to-innerhtml-when-using-lxml-html-to-parse-html

标签

python

parsing

lxml