Use XSL:Variable

Hello

I'm new at this List and new in XSL and I have many problems understanding how
to do something.

I have a XML that I want to transform to in a CSV text file to import to
Excel. Until now I have the text file like I want with the char set that I
want but there is something that I want and I don't know how.

In my XML I have a CONTROL tag with some information that I will use in the
other tags. Some of the tags in CONTROL tag will concatenate with some tags
along the rest the XML.

I have to get some data from the CONTROL tag and save it in a variable and use
to concatenate with fields is another tag.

How can I do that? I was trying to do like this.

     <xsl:template match="CONTROL">
          <xsl:apply-templates/>
     </xsl:template>
    
     <xsl:template match="ObjectFormat">
          <xsl:variable name="FileExtention"><xsl:value-of
select="@FileExtention"/></xsl:variable>
     </xsl:template>

The FileExtention is an Attribute of Object Format tag in CONTROL.

<xsl:template match="ObjectIndex">
     <xsl:value-of select="@Code"/><xsl:text>;</xsl:text>
     <xsl:value-of select="@Description"/><xsl:text>;</xsl:text>
     <xsl:copy-of select="$FileExtention" /><xsl:text>|</xsl:text>
     <xsl:text>&#xD;&#xA;</xsl:text>
</xsl:template>


With this XSL I get an error:
Invalid variable referenceError in XPath expression. Invalid variable
reference

How can I use this variable?

Tkx in advance

Paulo Aboim Pinto 
Engenheiro de Produto
======================
DSTS - Desenvolvimento e Integragco de Servigos e Tecnologia, S.A.
Tel.(+351)21 092 56 28
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