python - 求和所有 xml 标记值？

Question

此代码应该计算此 xml 文档中的评论数。

import urllib
import xml.etree.ElementTree as ET

url = 'http://python-data.dr-chuck.net/comments_42.xml'

print 'Retrieving', url
uh = urllib.urlopen(url)
data = uh.read()
print 'Retrieved',len(data),'characters'
print data
for line in data:
    tree = ET.fromstring(data)
    comments = tree.findall('comments')

    name = comments[0].find('comment').find('name').text
    count = comments[0].find('comment').find('count').text
    count = int(count)
    count = count + count
print count

但它只显示第一个comment标签上的评论数，然后将其添加到自己然后停止。

这是输出。上面是xml文档，下面是count(194，也就是97+97，只有 Romina)，这是不正确的。它应该是文件中所有评论的总和，而不仅仅是 Romina 的

如何获取文件中所有评论的总和？

Retrieving http://python-data.dr-chuck.net/comments_42.xml
Retrieved 4189 characters
<?xml version="1.0" encoding="UTF-8"?>
<commentinfo>
  <note>This file contains the sample data for testing</note>

  <comments>
    <comment>
       <name>Romina</name>
       <count>97</count>
    </comment>
    <comment>
       <name>Laurie</name>
       <count>97</count>
    </comment>
    <comment>
       <name>Bayli</name>
       <count>90</count>
    </comment>
    <comment>
       <name>Siyona</name>
       <count>90</count>
    </comment>
    <comment>
       <name>Taisha</name>
       <count>88</count>
    </comment>
    <comment>
       <name>Ameelia</name>
       <count>87</count>
    </comment>
    <comment>
       <name>Alanda</name>
       <count>87</count>
    </comment>
    <comment>
       <name>Prasheeta</name>
       <count>80</count>
    </comment>
</commentinfo>

194

Answer 1

注意细微的变化。因为<comments>包含几个 <comment>标签，我们首先需要找到所有的标签，然后我们才能遍历它们并找到 <count>标签。

import urllib
import xml.etree.ElementTree as ET

url = 'http://python-data.dr-chuck.net/comments_42.xml'

uh = urllib.urlopen(url)
data = uh.read()

tree = ET.fromstring(data)
comments = tree.find('comments').findall('comment')
total_count = 0
for comment in comments:
    count = comment.find('count').text
    count = int(count)
    total_count += count
print total_count
>> 2553