I have a solution, but it will not work perfectly

I get the sort by url parameters, for example:

http://yourdomain.com/categories/phones/xyz.aspx?sortby=[@alias = 'prize']&datatype=number&sortorder=ascending

http://yourdomain.com/categories/phones/xyz.aspx?sortby=@nodeName&datatype=number&sortorder=ascending

In the XSLT:

<xsl:param name="SortBy">
 <xsl:choose>
  <xsl:when test="umbraco.library:RequestQueryString('sortby') != ''">
   <xsl:value-of select="umbraco.library:RequestQueryString('sortby')" />
  </xsl:when>
  <xsl:otherwise>
   <xsl:text>@sortOrder</xsl:text>
  </xsl:otherwise>
 </xsl:choose>
</xsl:param>

<xsl:variable name="DataType">
 <xsl:choose>
  <xsl:when test="umbraco.library:RequestQueryString('datatype') != ''">
   <xsl:value-of select="umbraco.library:RequestQueryString('datatype')" />
  </xsl:when>
  <xsl:otherwise>
   <xsl:value-of select="'text'" />
  </xsl:otherwise>
 </xsl:choose>
</xsl:variable>

...

I will try to get [@alias = 'prize'] for <xsl:sort select="[@alias = 'prize']" ... /> with

<xsl:sort select="$SortBy" order="{$SortOrder}" data-type="{$DataType}"/>

but this doesn't work! Only

    <xsl:sort select="data[@alias = $SortBy]" order="{$SortOrder}" data-type="{$DataType}"/>

works for me, but here is the $SortBy prize or date but I need @nodeName, prize and date!

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