Return XPath attribute value with ElementTree

问题

I want to evaluate XML documents with this kind of structure:

<?xml version="1.0" encoding="UTF-8"?>
<Service_name version="3.3.0">
...

where Service_name tag name is not constant string, while version attribute is required.

For that purpose this xpath expression: /*[1]/@version evaluates fine with any xpath processor, but I can't figure how with Python ElementTree.

For example:

import xml.etree.ElementTree as ET
doc = ET.parse('sample.xml')
v = find('/*[1]/@version').text

raises KeyError: '@'

I tried similar combinations but none that worked.

How can I get version number from above example document with ElementTree?

回答1:

ElementTree uses its own path syntax, which is more or less a subset of xpath. If you want an ElementTree compatible library with full xpath support, try lxml.

回答2:

Although it's not XPath as question name, this seems like one way:

doc.getroot().get('version')

来源：https://stackoverflow.com/questions/12209092/return-xpath-attribute-value-with-elementtree