使用lxml解析html时没有根标记

Question

我一直在使用lxml和formalchemy为sqlalchemy构建一个脚手架库，并且我很难让它们很好地运行。具体而言，formalchemy.FieldSet.render()返回HTML的无根标签的片段，我似乎无法弄清楚如何获得LXML将其解析到的东西，可以包含到一个元素树：

我得到什么：

>>> 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：

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

我粗的变通：

>>> 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

要解析HTML，您需要使用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，则可以使用fragments_fromstring(string)，如here所述。