thanks doug.

i think for the short term i will go the xslt route, but i may go the .net route if i have any trouble with the strings.

thanks again!

just in case this is useful for anyone else, or if anyone wants to tell me that this is an absurd way to go about it, i ended up using the following:

xslt search results pass the term in the url 

page then calls macro with the following xslt. c# function carries out a case-insensitive replace for the search term.

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE xsl:stylesheet [
    <!ENTITY nbsp "&#x00A0;">
]>
<xsl:stylesheet version="1.0"
    xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
    xmlns:msxml="urn:schemas-microsoft-com:xslt"
    xmlns:msxsl="urn:schemas-microsoft-com:xslt"
    xmlns:umbraco.library="urn:umbraco.library"
    xmlns:fhd="urn:bl_ndp_lot:xslt"
    exclude-result-prefixes="msxml umbraco.library">

<xsl:output method="xml" omit-xml-declaration="yes" />
<xsl:param name="currentPage"/>
<xsl:template match="/">
    <xsl:variable name="source" select="$currentPage/data [@alias = 'bodyText']"/>
    <xsl:choose>
        <xsl:when test="string(umbraco.library:RequestQueryString('term')) != ''">
            <xsl:value-of select="fhd:ReplaceEx($source,string(umbraco.library:RequestQueryString('term')),'HOORAY')" disable-output-escaping="yes" />
        </xsl:when>
        <xsl:otherwise>
            <xsl:value-of select="$source" />::FINISHED::
        </xsl:otherwise>
    </xsl:choose>
</xsl:template>

<msxsl:script language="C#" implements-prefix="fhd">
<![CDATA[
    public static string ReplaceEx(string original, string pattern, string replacement)
    {
            int count, position0, position1;
            count = position0 = position1 = 0;
            string upperString = original.ToUpper();
        string upperPattern = pattern.ToUpper();
            int inc = (original.Length/pattern.Length) * (replacement.Length-pattern.Length);
            char [] chars = new char[original.Length + Math.Max(0, inc)];
            while( (position1 = upperString.IndexOf(upperPattern, position0)) != -1 )
            {
                for ( int i=position0 ; i < position1 ; ++i )
                    chars[count++] = original[i];
            for ( int i=0 ; i < replacement.Length ; ++i )
                chars[count++] = replacement[i];
                position0 = position1+pattern.Length;
            }
            if ( position0 == 0 ) return original;
            for ( int i=position0 ; i < original.Length ; ++i )
                chars[count++] = original[i];
            return new string(chars, 0, count);
    }
]]>
</msxsl:script>
</xsl:stylesheet>

i still need to sort out the multi word search terms, but this handles the single words just fine.

any thoughts anyone?

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