使用Python&lxm获取数据

Question

我有一个我的HTML，如下所示。我想得到<span class="zzAggregateRatingStat">中的文本。根据下面给出的示例，我可以得到3和5。在

对于这项工作，我使用Python2.7&lxml

<div class="pp-meta-review">
<span class="zrvwidget" style="">
    <span g:inline="true" g:type="NumUsersFoundThisHelpful" g:hideonnoratings="true" g:entity.annotation.groups="maps"    g:entity.annotation.id="http://maps.google.com/?q=Central+Kia+of+Irving++(972)+659-2204+loc:+1600+East+Airport+Freeway,+Irving,+TX+75062&gl=US&sll=32.83624,-96.92526" g:entity.annotation.author="AIe9_BH8MR-1JD_4BhwsKrGCazUyU5siqCtjchckDcg5BAl5rOLd9nvhJJDTrtjL-xFI8D42bD_7">
        <span class="zzNumUsersFoundThisHelpfulActive" zzlabel="helpful">
            <span>
                <span class="zzAggregateRatingStat">3</span>
            </span>
            <span>
                <span>&nbsp;</span>
                      out of
                <span>&nbsp;</span>
            </span>
            <span>
                <span class="zzAggregateRatingStat">5</span>
            </span>
            <span>
                <span>&nbsp;</span>
                    people found this review helpful.
            </span>
       </span>
   </span>
</span>
</div>

Answer 1

这是clearly documented at the lxml website

from lxml.etree import fromstring
from lxml.cssselect import CSSSelector

sel = CSSSelector('.zzAggregateRatingStat')
text = '<span><span class="zzAggregateRatingStat">3</span></span>'
doc = fromstring(text)
el = sel(doc)[0]
print el.text

Answer 2

以下代码适用于您的输入：

import lxml.html
root = lxml.html.parse('text.html').getroot()
for span in root.xpath('//span[@class="zzAggregateRatingStat"]'):
    print span.text

它打印：

^{pr2}$

我更喜欢使用lxml的xpath而不是cssselector，尽管它们都可以完成这项工作。在

ChrisP的示例打印3，但如果在实际输入上运行它，则会出现错误：

$ python chrisp.py
Traceback (most recent call last):
  File "chrisp.py", line 6, in <module>
    doc = fromstring(text)
  File "lxml.etree.pyx", line 2532, in lxml.etree.fromstring (src/lxml/lxml.etree.c:48270)
  File "parser.pxi", line 1545, in lxml.etree._parseMemoryDocument (src/lxml/lxml.etree.c:71812)
  File "parser.pxi", line 1424, in lxml.etree._parseDoc (src/lxml/lxml.etree.c:70673)
  File "parser.pxi", line 938, in lxml.etree._BaseParser._parseDoc (src/lxml/lxml.etree.c:67442)
  File "parser.pxi", line 539, in lxml.etree._ParserContext._handleParseResultDoc (src/lxml/lxml.etree.c:63824)
  File "parser.pxi", line 625, in lxml.etree._handleParseResult (src/lxml/lxml.etree.c:64745)
  File "parser.pxi", line 565, in lxml.etree._raiseParseError (src/lxml/lxml.etree.c:64088)
lxml.etree.XMLSyntaxError: EntityRef: expecting ';', line 3, column 210

ChrisP的代码可以改为使用lxml.html.fromstring，这是一个更为宽松的解析器，而不是{}。在

如果进行了此更改，它将打印3。在