具有嵌套元素的 Python LXML 迭代解析

Question

我想检索 XML 文件中特定元素的内容。然而，在 XML 元素中，还有其他 XML 元素，这会破坏父标记中内容的正确提取。一个例子：

xml = '''<?xml version='1.0' ?><test><claim-text><b>2</b>. A protective uniform for use by a person in combat or law enforcement, said uniform comprising: <claim-text>a. an upper body garment and a separate lower body garment</claim-text> <claim-text>b. a plurality of a ballistic and non-ballistic panels for attaching to the upper body garment and the lower body garment, and;</claim-text></claim-text></test>'''

context = etree.iterparse(StringIO(xml), events=('end',), tag='claim-text')
for event, element in context:
  print element.text

其结果是：

a. an upper body garment and a separate lower body garment
b. a plurality of a ballistic and non-ballistic panels for attaching to the upper body garment and the lower body garment, and;
None

然而，例如，“使用的防护制服..”被遗漏。似乎“声明文本”的每个元素（具有其他内部元素）都被忽略了。我应该如何更改 XML 的解析才能获取所有声明？

谢谢，

我刚刚用“普通”SAX 解析器方法解决了这个问题：

class SimpleXMLHandler(object):

  def __init__(self):
    self.buffer = ''
    self.claim = 0

  def start(self, tag, attributes):
    if tag == 'claim-text':
      if self.claim == 0:
        self.buffer = ''
      self.claim = 1

  def data(self, data):
    if self.claim == 1:
      self.buffer += data

  def end(self, tag):
    if tag == 'claim-text':
      print self.buffer
      self.claim = 0

  def close(self):
    pass

Answer 1

您可以使用 xpath 查找并连接直接在每个 节点下的所有文本节点，如下所示：

from StringIO import StringIO
from lxml import etree
xml = '''<?xml version='1.0' ?><test><claim-text><b>2</b>. A protective uniform for use by a person in combat or law enforcement, said uniform comprising: <claim-text>a. an upper body garment and a separate lower body garment</claim-text> <claim-text>b. a plurality of a ballistic and non-ballistic panels for attaching to the upper body garment and the lower body garment, and;</claim-text></claim-text></test>'''

context = etree.iterparse(StringIO(xml), events=('start',), tag='claim-text')
for event, element in context:
  print ''.join(element.xpath('text()'))

输出：

. A protective uniform for use by a person in combat or law enforcement, said uniform comprising:  
a. an upper body garment and a separate lower body garment
b. a plurality of a ballistic and non-ballistic panels for attaching to the upper body garment and the lower body garment, and;