不使用newlin在python中解析XML

Question

这是xml文件 http://www.diveintopython3.net/examples/feed.xml

我的python代码：

from lxml import etree
def lxml():
    tree = etree.parse('feed.xml')
    NSMAP = {"nn":"http://www.w3.org/2005/Atom"}
    test = tree.xpath('//nn:category[@term="html"]/..',namespaces=NSMAP)
    for elem in tree.iter():
        print(elem.tag,'\t',elem.attrib)
    print('-------------------------------')
    test1 = tree.xpath('//nn:category',namespaces=NSMAP)
    print('++++++++++++++++++++++++++++++++')
    for node in test1:
        test2 = node.xpath('./../nn:summary',namespaces=NSMAP) # return a list
        print(test2.xpath('normalize-space(.)'))
    print('*****************************************')
    test3 = tree.xpath('//text()[normalize-space(.)]')# [normalize-space()] only remove the heading and tailing
    print(test3)

输出为：。。你知道吗

++++++++++++++++++++++++++++++++
['Putting an entire chapter on one page sounds\n    bloated, but consider this — my longest chapter so far\n    would be 75 printed pages, and it loads in under 5 seconds…\n    On dialup.']
['Putting an entire chapter on one page sounds\n    bloated, but consider this — my longest chapter so far\n    would be 75 printed pages, and it loads in under 5 seconds…\n    On dialup.']
['Putting an entire chapter on one page sounds\n    bloated, but consider this — my longest chapter so far\n    would be 75 printed pages, and it loads in under 5 seconds…\n    On dialup.']
['The accessibility orthodoxy does not permit people to\n      question the value of features that are rarely useful and rarely used.']
['These notes will eventually become part of a\n      tech talk on video encoding.']
['These notes will eventually become part of a\n      tech talk on video encoding.']
['These notes will eventually become part of a\n      tech talk on video encoding.']
['These notes will eventually become part of a\n      tech talk on video encoding.']
['These notes will eventually become part of a\n      tech talk on video encoding.']
['These notes will eventually become part of a\n      tech talk on video encoding.']
['These notes will eventually become part of a\n      tech talk on video encoding.']
['These notes will eventually become part of a\n      tech talk on video encoding.']
*****************************************
['\n  ', 'dive into mark', '\n  ', 'currently between addictions', '\n  ', 'tag:diveintomark.org,2001-07-29:/', '\n  ', '2009-03-27T21:56:07Z', '\n  ', '\n  ', '\n  ', '\n    ', '\n      ', 'Mark', '\n      ', 'http://diveintomark.org/', '\n    ', '\n    ', 'Dive into history, 2009 edition', '\n    ', '\n    ', 'tag:diveintomark.org,2009-03-27:/archives/20090327172042', '\n    ', '2009-03-27T21:56:07Z', '\n    ', '2009-03-27T17:20:42Z', '\n    ', '\n    ', '\n    ', '\n  ', 'Putting an entire chapter on one page sounds\n    bloated, but consider this — my longest chapter so far\n    would be 75 printed pages, and it loads in under 5 seconds…\n    On dialup.', '\n  ', '\n  ', '\n    ', '\n      ', 'Mark', '\n      ', 'http://diveintomark.org/', '\n    ', '\n    ', 'Accessibility is a harsh mistress', '\n    ', '\n    ', 'tag:diveintomark.org,2009-03-21:/archives/20090321200928', '\n    ', '2009-03-22T01:05:37Z', '\n    ', '2009-03-21T20:09:28Z', '\n    ', '\n    ', 'The accessibility orthodoxy does not permit people to\n      question the value of features that are rarely useful and rarely used.', '\n  ', '\n  ', '\n    ', '\n      ', 'Mark', '\n    ', '\n    ', 'A gentle introduction to video encoding, part 1: container formats', '\n    ', '\n    ', 'tag:diveintomark.org,2008-12-18:/archives/20081218155422', '\n    ', '2009-01-11T19:39:22Z', '\n    ', '2008-12-18T15:54:22Z', '\n    ', '\n    ', '\n    ', '\n    ', '\n    ', '\n    ', '\n    ', '\n    ', '\n    ', 'These notes will eventually become part of a\n      tech talk on video encoding.', '\n  ', '\n']..

我的问题是为什么有这么多'\n'。如何删除它们？你知道吗

另外一个问题是如何直接查询文本的标签，比如make获取“Mark”节点（条目文本的子节点）。你知道吗

非常感谢

Answer 1

\n是一个转义序列。你知道吗

您可以检查页面源代码并发现bloated位于新行的开头。你知道吗

要删除它们，可以使用^{}或^{}。你知道吗

Answer 2

"My question is why there are so many '\n'. how to delete them?"

XML中的每个空格都将由XPath选择。格式良好的XML通常包含大量的换行符和空格。例如，在下面的XML中，有两个空文本节点将由//text()选择，即一个在<root>和<foo>之间，另一个在</foo>和</root>之间：

<root>
    <foo>bar</foo>
</root>

您可以使用//text()[normalize-space()]来避免首先选择空文本节点。你知道吗

"additional question is how to directly query the tag of a text, such as make to get the node of "Mark" ( the child of entry's text."

your_text_node.getparent().tag

上面应该获取变量your_text_node引用的文本节点的父元素，然后返回元素的标记名。你知道吗