使用for-each-group进行XSLT分组并使用填充元素

时间:2018-03-06 09:57:58

标签: xml xslt xpath xslt-2.0

我有一个人员列表,我想用每个人的名字对它们进行分组,然后检查哪个<vitalDates>节点有值,并将其放在分组<person>节点中。

<persons>
    <person>
        <name>Goethe, Johann Wolfgang von </name>
        <vitalDates>
            <earliest/>
            <latest/>
        </vitalDates>
    </person>
    <person>
        <name>Müthel, Lothar</name>
        <vitalDates>
            <earliest/>
            <latest/>
        </vitalDates>
    </person>
    <person>
        <name>Goethe, Johann Wolfgang von</name>
        <vitalDates>
            <earliest>1749</earliest>
            <latest>1832</latest>
        </vitalDates>
    </person>
    <person>
        <name>Müthel, Lothar</name>
        <vitalDates>
            <earliest>1896</earliest>
            <latest>1964</latest>
        </vitalDates>
    </person>
    <person>
        <name>Goethe, Johann Wolfgang von</name>
        <vitalDates>
            <earliest>1749</earliest>
            <latest>1832</latest>
        </vitalDates>
    </person>
</persons>

此刻我有这种转变:

<persons>
    <xsl:for-each-group select="person" group-by="name">
        <person>
            <name>
                <xsl:value-of select="current-grouping-key()"/>
            </name>
            <vitalDates>
                <earliest>
                    <xsl:for-each select="/persons/person[name=current-grouping-key()]/vitalDates/earliest">
                        <xsl:if test=". != ''">
                            <xsl:value-of select="."/>
                        </xsl:if>
                    </xsl:for-each>
                </earliest>
                <latest>
                    <!-- do the same? -->
                </latest>
            </vitalDates>
        </person>
    </xsl:for-each-group>
</persons>

我得到了这个结果:

<persons>
    <person>
        <name>Goethe, Johann Wolfgang von</name>
        <vitalDates>
            <earliest>17491749</earliest>
            <latest></latest>
        </vitalDates>
    </person>
    <person>
        <name>Müthel, Lothar</name>
        <vitalDates>
            <earliest></earliest>
            <latest></latest>
        </vitalDates>
    </person>
</persons>

就像你可以看到<earliest>元素的值被发现两次,但我只需要使用一个值,我不知道如何。

1 个答案:

答案 0 :(得分:1)

首先,当您使用for-each-group而不是/persons/person[name=current-grouping-key()]时,您可以而且应该只使用current-group()

至于选择第一项,请使用(current-group()/vitalDates/earliest[normalize-space()])[1]