Hi,

for designing a navigation bar a loop walks through all category names 
stored in a single document.
Inside Loop I'm using a key to ask a second document if the current 
categoryname also exists as pagename.
if yes, the output is the categoryname formated as HREF. if no, a 
dropdown-menu will created. this output
works fine.

the problem
HREF needs the current page-id corresponding the category-id. id-node 
"category" is the relation inside page
document.

my solution
using a second key (pageid) requesting the id corresponding to node 
'category' = $catid.
I think, concat() could make the criteria asking, but do not understand the 
correct using of it.

<xsl:variable name="dfile" select="document($datafile)"/>
<xsl:key name="pagename" match="siteinfo/pages/page/name" use="."/>
<xsl:key name="pageid" match="siteinfo/pages/page/id" use="concat(id, '+', 
category)"/>


<xsl:for-each 
select="document($categoryfile)//categories/category[visible!='off' and 
id!=0 and member='off']">
 <xsl:variable name="catname" select="catname"/>
 <xsl:variable name="catid" select="id"/>

 <xsl:variable name="pagename" select="$dfile[key('pagename', $catname)]"/>
 <xsl:variable name="pageid" select="$dfile[key('pageid', concat(id, 
$catid))]"/>

 <xsl:choose>
  <xsl:when test="$pagename">
   <xsl:if test="$pageid">
    ,"<xsl:value-of select="pageid" 
disable-output-escaping="yes"/><xsl:value-of select="$nbsp" 
disable-output-escaping="yes"/><xsl:value-of select="$not" 
disable-output-escaping="yes"/><xsl:value-of select="$nbsp" 
disable-output-escaping="yes"/><xsl:value-of 
select="$catname"/>","default.asp?id=<xsl:value-of 
select="id"/>&amp;mnu=<xsl:value-of select="id"/>","","<xsl:value-of 
select="$catname"/>",0
   </xsl:if>
  </xsl:when>
  <xsl:otherwise>
   ,"<xsl:value-of select="pageid" 
disable-output-escaping="yes"/><xsl:value-of select="$nbsp" 
disable-output-escaping="yes"/><xsl:value-of select="$not" 
disable-output-escaping="yes"/><xsl:value-of select="$nbsp" 
disable-output-escaping="yes"/><xsl:value-of 
select="$catname"/><xsl:value-of select="$nbsp" 
disable-output-escaping="yes"/>","show-menu=<xsl:value-of 
select="$catname"/>",,"",1
  </xsl:otherwise>
 </xsl:choose>

</xsl:for-each>

the input

pages
- <siteinfo>
 + <data>
 + <editorsettings>
 + <pages>
    + <page>
        - <name>
            <![CDATA[SERVICE]]
           </name>
        - <category>
            <![CDATA[1]]
          </category>
      </page>
    + <page>
   .
   .
   .

categorys
- <categories>
  - <category>
    <id>
    <![CDATA[1]]
   </id>
    <name>
    <![CDATA[SERVICE]]
   </name>
  </category>
  .
  .
  .


would be appreciated for advises.

christian schlemmer