Question

XML:

    <root>
<events>
    <event id="e1" v_id="v1">
        <elements></elements>
    </event>
    <event id="e1" v_id="v2">
        <elements></elements>
    </event>
    <event id="e1" v_id="v2">
        <elements></elements>
    </event>
</events>

<venues>
    <venue venue_id="v1">
        <venue_name></venue_name>
        <elements></elements>
    </venue>
    <venue venue_id="v2">
        <venue_name></venue_name>
        <elements></elements>
    </venue>
</root>

XSLT:

<xsl:template match="/">
        <xsl:apply-templates select="/root/events/event"/>
    </xsl:template>
    <xsl:template match="event">
        <xsl:value-of select="/root/venues/venue[@venue_id = /root/events/event/@v_id]/venue_name"/>
        <xsl:text>This is where I would like to put the venue name as a link to that venue</xsl:text>
    </xsl:template>

so if the v_id = v2 and the venue_id = v2 I want to display the value of venue_name from the venue with id = v2

Thanks

Answer 1

This is exactly the kind of issue that keys are designed to deal with.

In the root of your stylesheet, add

<xsl:key name="venue" match="venue" use="@venue_id" />

This effectively declares an associative array of all venue elements, indexed on their venue_id attribute. With this, you can get the venue element with any given venue_id attribute using the key function. I believe you can achieve what you need by substituting your <xsl:text> line with this:

<xsl:value-of select="key('venue', @v_id)/venue_name" />

This essentially looks up the right venue element, and gets the venue_name child within it.