The sample also allows you to test XPath queries against the mapping
schema. Two methods are used to show the results of the ASP XPath query.
In the first method, clicking the XPath with Parameter button
calls the ASP, which in turn filters the resulting XML document based on
the XPath the user supplies. This method calls the ASP page on the
server each time you press the XPath with Parameters button.
In the second method, clicking the Apply XSL button loads the XML
results from the ASP page into an XML data island. An Extensible
Stylesheet Language (XSL) transformation is performed upon the data
island and then displayed. Note that the ASP is not called until you
press the XPath with Parameter button, thereby calling the ASP.
follow this code-
http://support.microsoft.com/kb/272184