Question

I have been familiar with passing Input Param to XSLT CompiledTransformation class, so that parser takes care of XSL file making use of Param in processing instruction provided in XSL file.

Is there a way where we can get output param (say a value of node or something else) from XSLT to host language like C#??

XslCompiledTransform xslTransform = new XslCompiledTransform();

string strXmlOutput = string.Empty;
StringWriter swXmlOutput = null;
MemoryStream objMemoryStream = null;
XPathDocument xpathXmlOrig = new XPathDocument(string_xmlInput);
swXmlOutput = new StringWriter();
objMemoryStream = new MemoryStream();

xslArg.AddParam("TESTING", "", SomeVar);
XsltSettings xslsettings = new XsltSettings(false, true);

xslTransform.Load(string_xslInput, xslsettings, new XmlUrlResolver());
xslTransform.Transform(xpathXmlOrig, xslArg, objMemoryStream);

This code indeed outputs transformed XML, but my question is can we take just one value as output param from XSL Tranformation (XSLT file)??

Something like this:

xslArg.OutputParam("testing"); //Something like this?
........
........
xslTransform.Transform(xpathXmlOrig, xslArg, objMemoryStream);
string outputparam = xslArg.GetParam("testing"); //ideal way of getting param after traformation!

Does XSLT provides scope for something like this?

Answer 1

In C#, your best bet is to put <xsl:message> instructions in your XSLT code, and hook into the XsltMessageEncountered event on the XsltArgumentList class.

You can test it’s giving you the correct output without hooking the event, by watching the output of the app- in the absence of an event handler, messages are piped to standard output.