XsltMessageEncounteredEventArgs Class (System.Xml.Xsl)

Imports System
Imports System.IO
Imports System.Xml
Imports System.Xml.Xsl
Imports System.Xml.XPath

Public Class Sample    

  Public Shared Sub Main() 

    ' Create the XslCompiledTransform object and load the style sheet.
    Dim xslt As New XslCompiledTransform()
    xslt.Load("message.xsl")

    Dim argList As New XsltArgumentList()
    AddHandler argList.XsltMessageEncountered, AddressOf MessageCallBack

    ' Load the file to transform.
    Dim doc As New XPathDocument("books.xml")

    ' Transform the file.
    xslt.Transform(doc, argList, XmlWriter.Create("output.xml"))

  End Sub 'Main     

  Private Shared Sub MessageCallBack(ByVal sender As Object, ByVal e As XsltMessageEncounteredEventArgs) 
    Console.WriteLine("Message received: {0}", e.Message)

  End Sub 'MessageCallBack
End Class 'Sample 

using System;
using System.IO;
using System.Xml;
using System.Xml.Xsl;
using System.Xml.XPath;

public class Sample {

  public static void Main() {

    // Create the XslCompiledTransform object and load the style sheet.
    XslCompiledTransform xslt = new XslCompiledTransform();
    xslt.Load("message.xsl");

    XsltArgumentList argList = new XsltArgumentList();
    argList.XsltMessageEncountered += new XsltMessageEncounteredEventHandler(MessageCallBack);
	
    // Load the file to transform.
    XPathDocument doc = new XPathDocument("books.xml");

    // Transform the file.
    xslt.Transform(doc, argList, XmlWriter.Create("output.xml"));

  }

  private static void MessageCallBack(object sender, XsltMessageEncounteredEventArgs e) {
    Console.WriteLine("Message received: {0}", e.Message);
  }

}

<bookstore>
  <book genre="autobiography" publicationdate="1981" ISBN="1-861003-11-0">
    <title>The Autobiography of Benjamin Franklin</title>
    <author>
      <first-name>Benjamin</first-name>
      <last-name>Franklin</last-name>
    </author>
    <price>8.99</price>
  </book>
  <book genre="novel" publicationdate="1967" ISBN="0-201-63361-2">
    <title>The Confidence Man</title>
    <author>
      <first-name>Herman</first-name>
      <last-name>Melville</last-name>
    </author>
    <price>11.99</price>
  </book>
  <book genre="philosophy" publicationdate="1991" ISBN="1-861001-57-6">
    <title>The Gorgias</title>
    <author>
      <name>Plato</name>
    </author>
    <price>9.99</price>
  </book>
</bookstore>

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">
  <xsl:output method="xml" omit-xml-declaration="yes"/>

<xsl:template match="/">
     <xsl:apply-templates select="*"/>
     <xsl:copy-of select="."/>
  </xsl:template>

  <xsl:template match="*">
     <xsl:apply-templates select="//author"/>
  </xsl:template>

  <xsl:template match="author">
    <xsl:if test="not (last-name)">
       <xsl:message terminate="no">Author name is not in the correct format <xsl:copy-of select="."/>
       </xsl:message>
    </xsl:if>
  </xsl:template>

</xsl:stylesheet>