XPATH：嵌套选择

Question

我们想构建一个XPath表达式，为每个站点选择 transportmittel_detail 节点。

我们目前的做法如下：

sbb/station[name="Winterthur"]/transportmittel/../../transportmittel_detail/transportmittel[name=text()]

sbb/station[name="Winterthur"]/transportmittel 返回

<transportmittel>S12</transportmittel> <transportmittel>B1</transportmittel> <transportmittel>B2</transportmittel>

问题：

我们如何编写第二个条件，以便 text（）等于 S12，B1，B2。

完整的XML如下所示：

<?xml version="1.0" encoding="UTF-8"?>
<sbb>
    <station>
        <name>Zürich, Schwamendingerplatz</name>
        <coordinates>
            <lat>47.4042</lat>
            <long>8.5739</long>
            <height>434</height>
        </coordinates>
        <transportmittel>T7</transportmittel>
        <transportmittel>T9</transportmittel>
    </station>
    <station>
        <name>Winterthur</name>
        <coordinates>
            <lat>47.5003</lat>
            <long>47.5003</long>
            <height>466</height>
        </coordinates>
        <transportmittel>S12</transportmittel>
        <transportmittel>B1</transportmittel>
        <transportmittel>B2</transportmittel>
    </station>
    <station>
        <name>Stettbach, Bahnhof</name>
        <coordinates>
            <lat>47.3972</lat>
            <long>8.5961</long>
            <height>437</height>
        </coordinates>
        <transportmittel>S12</transportmittel>
        <transportmittel>T7</transportmittel>
        <transportmittel>T12</transportmittel>
        <transportmittel>B760</transportmittel>
    </station>
    <schedule>
        <connection>
            <from>Zürich, Schwamendingerplatz</from>
            <to>Stettbach, Bahnhof</to>
            <departure>08:43</departure>
            <arrival>08:48</arrival>
            <transportmittel>T7</transportmittel>
        </connection>
        <connection>
            <from>Stettbach, Bahnhof</from>
            <to>Winterthur</to>
            <departure>08:56</departure>
            <arrival>09:09</arrival>
            <track_departure>2</track_departure>
            <track_arrival>5</track_arrival>
            <transportmittel>S12</transportmittel>
        </connection>
    </schedule>
    <transportmittel_detail>
        <transportmittel>
            <name>T7</name>
            <departure>Zürich, Wollishofen</departure>
            <arrival>Stettbach, Bahnhof</arrival>
        </transportmittel>
        <transportmittel>
            <name>S12</name>
            <departure>Brugg AG</departure>
            <arrival>Winterthur, Seen</arrival>
        </transportmittel>
    </transportmittel_detail>
</sbb>

Answer 1

使用（XPath 1.0）：

/sbb/transportmittel_detail [transportmittel/name = /sbb/station[name='Winterthur']/transportmittel]

或此XPath 2.0表达式：

for $station in /sbb/station[name='Winterthur'] return /sbb/transportmittel_detail[transportmittel/name = $station/transportmittel]

Answer 2

如果您使用/sbb/transportmittel_detail/transportmittel[name = /sbb/station[name="Winterthur"]/transportmittel]，则选择transportmittel等于任何name元素的/sbb/station[name="Winterthur"]/transportmittel元素。