I don't know of a way to call out of XSL into your ASP.NET code. Not sure its possible.
However, you can have code inside your XSL--even C# or VB.NET code provided you are running ASP.NET (which you are).
I have a small example of how this is done here:
http://www.braintrove.com/default.aspx?p=3&s=1&i=8
The example uses JavaScript, but you can just as easily convert the language used to C# or whatever. I do this all the time with my site development.
--
Greg Collins [Microsoft MVP]
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