XSL for-each: how to detect last node?

I have this simple code:

<xsl:for-each select="GroupsServed">
  <xsl:value-of select="."/>,<br/>
</xsl:for-each></font>

I'm trying to add a comma for each item added.

This has 2 flaws:

1. Case of when there's only 1 item: th开发者_JS百科e code would unconditionally add a comma.
2. Case of when there's more than 1 item: the last item would have a comma to it.

What do you think is the most elegant solution to solve this?

I'm using XSLT 2.0

If you're using XSLT 2.0, the canonical answer to your problem is

<xsl:value-of select="GroupsServed" separator=", " />

On XSLT 1.0, the somewhat CPU-expensive approach to finding the last element in a node-set is

<xsl:if test="position() = last()" />

Final answer:

<xsl:for-each select="GroupsServed">
  <xsl:value-of select="."/>                                    
  <xsl:choose>
    <xsl:when test="position() != last()">,<br/></xsl:when>
  </xsl:choose>
</xsl:for-each>

<xsl:variable name="GROUPS_SERVED_COUNT" select="count(GroupsServed)"/>
<xsl:for-each select="GroupsServed">
    <xsl:value-of select="."/>
    <xsl:if test="position() < $GROUPS_SERVED_COUNT">
        ,<br/>
    </xsl:if>
</xsl:for-each></font>

Insert the column delimiter before each new item, except the first one. Then insert the line break outside the for-each loop.

<xsl:for-each select="GroupsServed">
  <xsl:if test="position() != 1">,</xsl:if>
  <xsl:value-of select="."/>
</xsl:for-each>
<br/>

In other words, treat every item like the last item. The exception is that the first item does not need a comma separator in front of it. The loop ends after the last item is processed, which also tells us where to put the break.