当每个元素中有多个条目时如何使用python ElementTree读取XML

Question

已编辑以包含一些额外信息

我有一些 XML 格式的数据，我已经设法在 Python 中使用 ElementTree 解析了这些数据。在主数据的每一行中都有一个名为volume 的标签，然后是一组数据，然后我将其放入一个数组中（我后来将其保存为熊猫数据框）。我遇到的问题是我需要知道我正在调用字段名称的条目的名称（即 [message, messagetimestamp,settlementdate,settlementperiod,etc...] 能够调用数据。

我想使用一些代码来告诉我该字段名称列表是什么，而不是手动输入它们。我在这里的 XML 术语可能有误，但数据看起来像所附图像。

XML 作为文本：

<response xmlns="http://www.netareports.com/backend/realtime" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.netareports.com/backend/realtime http://www.netareports.com/backend/realtime.xsd" status="1" timestamp="2021-03-19T16:37:23">
<periodacceptedvolume message="BMRS.DISPTAV" messagetimestamp="2020-11-30T01:52:32" settlementdate="2020-11-30T00:00:00" settlementperiod="3" bmunitid="E_GYAR-1" bidofferpairnumber="-1" offervolume="0" bidvolume="-44.75" taggedoffervolume="0" repricedoffervolume="0" originallypricedoffervolume="0" taggedbidvolume="-44.531" repricedbidvolume="0" originallypricedbidbolume="-43.69"/>
<periodacceptedvolume message="BMRS.DISPTAV" messagetimestamp="2020-11-30T01:52:32" settlementdate="2020-11-30T00:00:00" settlementperiod="3" bmunitid="T_DAMC-1" bidofferpairnumber="1" offervolume="240" bidvolume="0" taggedoffervolume="240" repricedoffervolume="0" originallypricedoffervolume="0" taggedbidvolume="0" repricedbidvolume="0" originallypricedbidbolume="0"/>
<periodacceptedvolume message="BMRS.DISPTAV" messagetimestamp="2020-11-30T01:52:32" settlementdate="2020-11-30T00:00:00" settlementperiod="3" bmunitid="T_DIDCB6" bidofferpairnumber="1" offervolume="220" bidvolume="0" taggedoffervolume="220" repricedoffervolume="0" originallypricedoffervolume="0" taggedbidvolume="0" repricedbidvolume="0" originallypricedbidbolume="0"/>
<periodacceptedvolume message="BMRS.DISPTAV" messagetimestamp="2020-11-30T01:52:32" settlementdate="2020-11-30T00:00:00" settlementperiod="3" bmunitid="T_DINO-6" bidofferpairnumber="-1" offervolume="0" bidvolume="-2.592" taggedoffervolume="0" repricedoffervolume="0" originallypricedoffervolume="0" taggedbidvolume="-2.592" repricedbidvolume="0" originallypricedbidbolume="0"/>
<periodacceptedvolume message="BMRS.DISPTAV" messagetimestamp="2020-11-30T01:52:32" settlementdate="2020-11-30T00:00:00" settlementperiod="3" bmunitid="T_MEDP-1" bidofferpairnumber="1" offervolume="170" bidvolume="0" taggedoffervolume="170" repricedoffervolume="0" originallypricedoffervolume="0" taggedbidvolume="0" repricedbidvolume="0" originallypricedbidbolume="0"/>

我用来阅读的代码是：

    import xml.etree.ElementTree as ET
    import urllib.request

    url = #not included as it includes a password but the XML data is copied from the url
    download = urllib.request.urlopen(url).read()
    tree = ET.fromstring(download)

    fieldsV=['message','messagetimestamp','settlementdate','settlementperiod','bmunitid','bidofferpairnumber','offervolume','bidvolume','taggedoffervolume','repricedoffervolume','originallypricedoffervolume','taggedbidvolume','repricedbidvolume','originallypricedbidbolume']
    data = []
    for child in tree:
        data.append([(child.get(name) or '') for name in fields])

这工作正常，但fields 是我手动输入的列表，我想使用代码生成列表，以便可以将其应用于其他类似的 XML 文件。任何帮助将不胜感激！

Answer 1

假设 XML 根的所有子元素（本例中为 periodacceptedvolume 元素）包含相同的属性列表，您只需获取该元素的一个样本并从那里读取属性名称列表：

....
tree = ET.fromstring(download)

sample_node = tree.find('*')
fieldsV=[a for a in sample_node.attrib]
....