没有根标记时使用lxml进行html解析

Question

我一直在使用lxml和formalchemy为sqlalchemy构建一个脚手架库，我很难让它们很好地发挥作用。具体地说，formalchemy.FieldSet.render()返回一个没有根标记的html片段，而我似乎不知道如何让lxml将其解析成可以包含在元素树中的内容：

我得到的是：

>>> lxml.etree.fromstring(formalchemy.FieldSet(toyschema.User(), session).render())
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "lxml.etree.pyx", line 2743, in lxml.etree.fromstring (src/lxml/lxml.etree.c:52665)
  File "parser.pxi", line 1573, in lxml.etree._parseMemoryDocument (src/lxml/lxml.etree.c:79932)
  File "parser.pxi", line 1445, in lxml.etree._parseDoc (src/lxml/lxml.etree.c:78709)
  File "parser.pxi", line 920, in lxml.etree._BaseParser._parseUnicodeDoc (src/lxml/lxml.etree.c:75083)
  File "parser.pxi", line 564, in lxml.etree._ParserContext._handleParseResultDoc (src/lxml/lxml.etree.c:71739)
  File "parser.pxi", line 645, in lxml.etree._handleParseResult (src/lxml/lxml.etree.c:72614)
  File "parser.pxi", line 585, in lxml.etree._raiseParseError (src/lxml/lxml.etree.c:71955)
lxml.etree.XMLSyntaxError: Extra content at the end of the document, line 8, column 1

我想要的：

>>> ?????(formalchemy.FieldSet(toyschema.User(), session).render())
[<Element div at 0x1e48e10>, <Element script at 0x1e48cd0>, <Element div at 0x1e48730>, <Element div at 0x1ea1e60>]

我粗略的解决办法：

>>> lxml.etree.fromstring('<root>%s</root>' % formalchemy.FieldSet(toyschema.User(), session).render()).getchildren()
[<Element div at 0x1e48e10>, <Element script at 0x1e48cd0>, <Element div at 0x1e48730>, <Element div at 0x1ea1e60>]

Answer 1

为了解析超文本标记语言，你需要使用lxml.html，而不是lxml.etree。

如果您想要一个片段列表，而不是将它们包装在div中，您可以使用fragments_fromstring(string)，如here所述。