具有特定元素的编辑XML文件

Question

因此，在python中，我需要读写XML数据库。我已经完成了读取部分，但我很难找到只将数据写入具有特定元素的节点的方法。

这应该能把事情弄清楚

 <team>
    <number>78</number>
    <matches_played>0</matches_played>
    <matches_played>0</matches_played>
    <start_position>1</start_position>
    <preloaded_ball>0</preloaded_ball>
    <high_goals_made_auto>0</high_goals_made_auto>
    <low_goals_made_auto>0</low_goals_made_auto>
    <shots_missed_auto>0</shots_missed_auto>
    <hot_goal_bonus_auto>0</hot_goal_bonus_auto>
    <moved_bonus_auto>0</moved_bonus_auto>
    <high_goals_made_tel>0</high_goals_made_tel>
    <low_goals_made_tel>0</low_goals_made_tel>
    <shots_missed_tel>0</shots_missed_tel>
    <balls_received_tel>0</balls_received_tel>
    <balls_passed_tel>0</balls_passed_tel>
    <truss_shots_tel>0</truss_shots_tel>
    <catches_tel>0</catches_tel>


</team>

<team>
    <number>195</number>
    <matches_played>0</matches_played>
    <matches_played>0</matches_played>
    <start_position>1</start_position>
    <preloaded_ball>0</preloaded_ball>
    <high_goals_made_auto>0</high_goals_made_auto>
    <low_goals_made_auto>0</low_goals_made_auto>
    <shots_missed_auto>0</shots_missed_auto>
    <hot_goal_bonus_auto>0</hot_goal_bonus_auto>
    <moved_bonus_auto>0</moved_bonus_auto>
    <high_goals_made_tel>0</high_goals_made_tel>
    <low_goals_made_tel>0</low_goals_made_tel>
    <shots_missed_tel>0</shots_missed_tel>
    <balls_received_tel>0</balls_received_tel>
    <balls_passed_tel>0</balls_passed_tel>
    <truss_shots_tel>0</truss_shots_tel>
    <catches_tel>0</catches_tel>


</team> 

正如您所看到的，两者都是<team>，而且它们都有一个<number>，我如何只在<number>78</number>中编辑元素？

Answer 1

下面是一个简单的生成器表达式，您可以使用它查找包含带有text = 78的number元素的team元素

tree = ET.fromstring(data)
team = next(team for team in tree.iter('team') 
            for number in team.iter('number') 
            if number.text == '78')

team.find('.//high_goals_made_tel').text = "I've changed"
print ET.tostring(tree)

其中data是您的xml。

而且，仅仅是FYI，使用lxml的解决方案看起来要容易得多，因为它有完全的xpath支持：

from lxml import etree
from lxml.etree import XMLParser

data = """..."""

tree = etree.fromstring(data, parser=XMLParser())
team = tree.xpath('.//number[text()="78"]/..')[0]
team.find('high_goals_made_tel').text = "I've changed"

print etree.tostring(tree)