相关疑难解决方法(0)

我需要使用python的lxml基于属性的内容完全删除元素.例:

import lxml.etree as et

xml="""
<groceries>
  <fruit state="rotten">apple</fruit>
  <fruit state="fresh">pear</fruit>
  <fruit state="fresh">starfruit</fruit>
  <fruit state="rotten">mango</fruit>
  <fruit state="fresh">peach</fruit>
</groceries>
"""

tree=et.fromstring(xml)

for bad in tree.xpath("//fruit[@state=\'rotten\']"):
  #remove this element from the tree

print et.tostring(tree, pretty_print=True)

我想要打印:

<groceries>
  <fruit state="fresh">pear</fruit>
  <fruit state="fresh">starfruit</fruit>
  <fruit state="fresh">peach</fruit>
</groceries>

有没有办法在不存储临时变量并手动打印的情况下执行此操作,如下所示:

newxml="<groceries>\n"
for elt in tree.xpath('//fruit[@state=\'fresh\']'):
  newxml+=et.tostring(elt)

newxml+="</groceries>"

我如何在XPath 1.0中找到所有空行col name="POW"？

<row>
<col name="WOJ">02</col>
<col name="POW"/>
<col name="GMI"/>
<col name="RODZ"/>
<col name="NAZWA">DOLNO?L?SKIE</col>
<col name="NAZDOD">województwo</col>
<col name="STAN_NA">2011-01-01</col>
</row>

我试过很多解决方案.在Firefox扩展XPath Checker选择中很少次,但lxml.xpath()表示表达式无效或只返回没有行.

我的Python代码:

from lxml import html
f = open('TERC.xml', 'r')
page = html.fromstring(f.read())
for r in page.xpath("//row[col[@name = 'POW' and not(text())]]"):
    print r.text_content()
    print "-------------------------"