Have a look at this: http://our.umbraco.org/wiki/reference/xslt/extend-your-xslt-with-custom-functions

Instead of using C#, you can use Javascript if you wish.

I don't believe that you can use javascript as of Umbraco 4

You can, e.g. I placed the following code into my search xslt for paging support:

<script type="text/javascript">
var content = [
<xsl:for-each select="$results/SearchResult">
  <xsl:sort select="@createDate" order="descending"/>
 ['<xsl:value-of select="@text" />','<xsl:value-of select="@linkUrl" />']
<xsl:if test="position() != last()">,</xsl:if>
  </xsl:for-each>
];

<xsl:text disable-output-escaping="yes">
  function pageselectCallback(page_index, jq){
                var items_per_page = 5;
                var max_elem = Math.min((page_index+1) * 5, content.length);
                var newcontent = '';
                
                for(var i=page_index*items_per_page;i &lt; max_elem; i++)
                {
                    newcontent += '&lt;li&gt;' + content[i][0] + '&lt;/li&gt;';
                }
                
                $('#SearchPagerContent').html(newcontent);
                
                return false;
            }
</xsl:text>

      $("#SearchPager").pagination(content.length, {
     items_per_page:5, 
        callback:pageselectCallback
   });

</script>

hth,

Thomas

But to have the active li marked you can do this via css and classes for the li. Or just look into the http://our.umbraco.org/projects/cogworks---flexible-navigation project

Thomas

Something like this?

<style  media="all" type="text/css" >
#nav-main li{float:left; display:block; padding:0px; margin:0px; list-style:none; border-right:1px dotted #333;}
#nav-main li a{ display:block; float:left; background:#ccc; color:#000; padding:20px; }
#nav-main li a:hover{background:#000; color:#fff}
</style>

<ul id="nav-main">
<li><a href="http://google.com" >Google</a></li>
<li><a href="http://yahoo.com" >Yahoo</a></li>
<li><a href="http://bbc.co.uk" >BBC</a></li>
</ul>

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