How to pass as variable into .xslt 1.0 key expressions - xslt

Question

Following on from my original question:
Filtering, Grouping, Counting and Selecting specific nodes in XML using XSLT 1.0
I've now run into another problem. Using this code that was kindly provided by michael.hor257k
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="text" encoding="UTF-8"/>
<xsl:key name="vehicle-by-series" match="Vehicle[Model='KA']" use="Series" />
<xsl:template match="/Dealer">
<xsl:for-each select="Vehicle[Model='KA'][count(. | key('vehicle-by-series', Series)[1]) = 1]">
<xsl:value-of select="Model"/>
<xsl:text>: </xsl:text>
<xsl:value-of select="Series"/>
<xsl:text>, </xsl:text>
<xsl:variable name="grp" select="key('vehicle-by-series', Series)" />
<xsl:value-of select="count($grp)"/>
<xsl:text> in stock, starting from </xsl:text>
<xsl:for-each select="$grp">
<xsl:sort select="Price" data-type="number" order="ascending"/>
<xsl:if test="position() = 1">
<xsl:value-of select="Price"/>
</xsl:if>
</xsl:for-each>
<xsl:text>
</xsl:text>
</xsl:for-each>
</xsl:template>
</xsl:stylesheet>
I'm passing in the parameter model:
<xsl:param name="model" />
From an asp.NET URL variable.
I want to substitute the currently hardcoded KA for the model parameter. From the searching I've done you can't use parameters or variables in a key expression in XSLT 1.0. And I don't have the option to upgrade to 2.0. Mores the pity.
Would really appreciate some more help please.
Thanks in advance.

Answer 1

I would suggest you do:
XSLT 1.0
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="text" encoding="UTF-8"/>
<xsl:param name="model"/>
<xsl:key name="vehicle-by-series" match="Vehicle" use="concat(Model, '|', Series)" />
<xsl:template match="/Dealer">
<xsl:for-each select="Vehicle[Model=$model][count(. | key('vehicle-by-series', concat(Model, '|', Series))[1]) = 1]">
<xsl:value-of select="Model"/>
<xsl:text>: </xsl:text>
<xsl:value-of select="Series"/>
<xsl:text>, </xsl:text>
<xsl:variable name="grp" select="key('vehicle-by-series', concat(Model, '|', Series))" />
<xsl:value-of select="count($grp)"/>
<xsl:text> in stock, starting from </xsl:text>
<xsl:for-each select="$grp">
<xsl:sort select="Price" data-type="number" order="ascending"/>
<xsl:if test="position() = 1">
<xsl:value-of select="Price"/>
</xsl:if>
</xsl:for-each>
<xsl:text>
</xsl:text>
</xsl:for-each>
</xsl:template>
</xsl:stylesheet>