使用etree查找xml文件中内部文本的所有出现

Question

I am new to python and trees at all, and have encountered some problems.

I have the following dataset structured as:

<?xml version="1.0" encoding="UTF-8"?>
<graphml xmlns="http://graphml.graphdrawing.org/xmlns">
  <node id="node1">
    <data key="label">node1</data>
    <data key="degree">6</data>
  </node>
  <node id="node2">
    <data key="label">node2</data>
    <data key="degree">32</data>
  </node>
  <node id="node3">
    <data key="label">node3</data>
    <data key="degree">25</data>
  </node>
</graphml>

I wish to be able to reach and print all the inner text of the < data key="label"> elements using etree. In other words get the following result:

"node1"
"node2"
"node3"

I have tried the itertext() with no luck ( https://docs.python.org/2/library/xml.etree.elementtree.html#xml.etree.ElementTree.Element.itertext ), as well as faulty xpath expressions.

I'm sure there is a simple solution to this, hope you guys can help!

Answer 1

You probably forget the namespace. Try something like this:

import xml.etree.ElementTree as ET

root = ET.fromstring(countrydata)

ns = {'graphml': 'http://graphml.graphdrawing.org/xmlns'}

for element in root.findall(".//graphml:node[@id]",ns):
    print(element.attrib['id'])

Answer 2

This does the job on python 2.7 :

import xml.etree.ElementTree as ET
root = ET.fromstring(data)

elts = root.findall('.//*[@key="label"]')
for e in elts:
    print(e.text)