Question

It seems like this is easy to do in XSLT 2.0 but Microsoft in its infinite wisdom doesn’t support XSLT 2.0 in Visual Studio 2005.

Answer 1

One option would be to do all the parsing and calculation in XSLT.

However, another option would be to extend XSLT with a custom script function in C#:

<?xml version='1.0' encoding='utf-8'?> <xsl:stylesheet version='1.0'                 xmlns:xsl='http://www.w3.org/1999/XSL/Transform'                 xmlns:msxsl='urn:schemas-microsoft-com:xslt'                 xmlns:myext='urn:myExtension'                 exclude-result-prefixes='msxsl myext'>    <xsl:output method='xml' indent='yes'/>    <msxsl:script language='C#' implements-prefix='myext'>      <![CDATA[          public int SecondsFromIsoDuration(string isoDuration)         {             // parse and convert here;         }      ]]>    </msxsl:script>     <xsl:template match='@* | node()'>     <root durationInSeconds='{myext:SecondsFromIsoDuration(@duration)}' />   </xsl:template> </xsl:stylesheet> 

The script function will be compiled at runtime to a temporary assembly and then executed. However, be aware to cache your XSLT because every XSLT-compilation will create a new assembly which is only unloaded when your application exits.