假设我们有一个结构如下的 XML 文件。
<?xml version="1.0" ?>
<searchRetrieveResponse xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.loc.gov/zing/srw/ http://www.loc.gov/standards/sru/sru1-1archive/xml-files/srw-types.xsd" xmlns="http://www.loc.gov/zing/srw/">
<records xmlns:ns1="http://www.loc.gov/zing/srw/">
<record>
<recordData>
<record xmlns="">
<datafield tag="000">
<subfield code="a">123</subfield>
<subfield code="b">456</subfield>
</datafield>
<datafield tag="001">
<subfield code="a">789</subfield>
<subfield code="b">987</subfield>
</datafield>
</record>
</recordData>
</record>
<record>
<recordData>
<record xmlns="">
<datafield tag="000">
<subfield code="a">123</subfield>
<subfield code="b">456</subfield>
</datafield>
<datafield tag="001">
<subfield code="a">789</subfield>
<subfield code="b">987</subfield>
</datafield>
</record>
</recordData>
</record>
</records>
</searchRetrieveResponse>
我需要解析:
- “子字段”的内容(例如上例中的 123)和
- 属性值(例如 000 或 001)
我想知道如何使用 lxml 和 XPath 来做到这一点。下面粘贴的是我的初始代码,我恳请有人解释一下,如何解析出值。
import urllib, urllib2
from lxml import etree
url = "https://dl.dropbox.com/u/540963/short_test.xml"
fp = urllib2.urlopen(url)
doc = etree.parse(fp)
fp.close()
ns = {'xsi':'http://www.loc.gov/zing/srw/'}
for record in doc.xpath('//xsi:record', namespaces=ns):
print record.xpath("xsi:recordData/record/datafield[@tag='000']", namespaces=ns)