XMLStarlet：每个项目打印一行，同时使用父元素的数据

Question

我有以这种方式格式化的 XML 数据：

<XML>
    <Waveforms Time="01/01/2009 3:00:02 AM">
        <WaveformData Channel="I">1, 2, 3, 4, 5, 6 </WaveformData>
        <WaveformData Channel="II">9, 8, 7, 6, 5, 4 </WaveformData>
    </Waveforms>
    <Waveforms Time="01/01/2009 3:00:04 AM">
        <WaveformData Channel="I">1, 2, 3, 4, 5, 6 </WaveformData>
        <WaveformData Channel="II">9, 8, 7, 6, 5, 4 </WaveformData>
    </Waveforms>
</XML>

我正在尝试使用 xmlstarlet 将此数据解析为文本文件（逗号分隔）。所需的输出如下所示：

Time Attribute, Channel Attribute, Data
01/01/2009 3:00:02 AM, I, 1, 2, 3, 4, 5, 6
01/01/2009 3:00:02 AM, II, 9, 8, 7, 6, 5, 4
01/01/2009 3:00:02 AM, I, 1, 2, 3, 4, 5, 6
01/01/2009 3:00:02 AM, II, 9, 8, 7, 6, 5, 4

我能想到的最好的是：

 xmlstarlet sel -T -t -m //XML/Waveforms -v @Time -o "," -m Waves -v WaveformData/@Channel -o "," -v WaveformData -o "," -b -n testwave2.xml > testwave.txt

这给出了这样的结果：

 01/01/2009 3:00:02 AM, I, 1, 2, 3, 4, 5, 6, II, 9, 8, 7, 6, 5, 4
 01/01/2009 3:00:04 AM, I, 1, 2, 3, 4, 5, 6, II, 9, 8, 7, 6, 5, 4

很清楚如何为每个 Waveforms 打印一行，但如果我想包含其父级的 time 属性，则不清楚如何为每个 WaveformData 打印一行。这能做到吗？或者，我应该解决并进行一些切片和粘贴以在后端修复它吗？

Answer 1

搜索 WaveformData - 因为它是你想要的每一个 - 并在树中向上遍历以找到您的时间元素。

$ xmlstarlet sel -T -t -m /XML/Waveforms/WaveformData \
     -v ../@Time -o "," \
     -v @Channel -o "," \
     -v . -n <in.xml
01/01/2009 3:00:02 AM,I,1, 2, 3, 4, 5, 6 
01/01/2009 3:00:02 AM,II,9, 8, 7, 6, 5, 4 
01/01/2009 3:00:04 AM,I,1, 2, 3, 4, 5, 6 
01/01/2009 3:00:04 AM,II,9, 8, 7, 6, 5, 4 

或者，如果您知道每个 Waveforms 将恰好有两个 WaveformData 子级，则可以执行以下操作：

$ xmlstarlet sel -T -t -m /XML/Waveforms \
    -v ./@Time -o ",I,"  -v './WaveformData[@Channel="I"]' -n \
    -v ./@Time -o ",II," -v './WaveformData[@Channel="II"]' -n <in.xml
01/01/2009 3:00:02 AM,I,1, 2, 3, 4, 5, 6
01/01/2009 3:00:02 AM,II,9, 8, 7, 6, 5, 4
01/01/2009 3:00:04 AM,I,1, 2, 3, 4, 5, 6
01/01/2009 3:00:04 AM,II,9, 8, 7, 6, 5, 4