Template Messages Using XSL Transformations and XML Serialization

using System;
using System.IO;
using System.Xml;
using System.Xml.Serialization;
using System.Xml.Xsl;

namespace TemplatesExample
{
    internal class Transformer
    {
        private XslCompiledTransform mXslTransformer;
        private event EventHandler<ObjectSerializedEventArgs> mObjectSerialized;

        public event EventHandler<ObjectSerializedEventArgs> ObjectSerialized
        {
            add { mObjectSerialized += value; }
            remove { mObjectSerialized -= value; }
        }

        private void RaiseObjectSerializedEvent(Stream serializedObject)
        {
            EventHandler<ObjectSerializedEventArgs> objectSerialized = mObjectSerialized;

            if (objectSerialized != null)
            {
                Stream cloning = CloneStream(serializedObject);
                ObjectSerializedEventArgs args = new ObjectSerializedEventArgs(cloning);
                objectSerialized(this, args);
            }
        }

        private static Stream CloneStream(Stream original)
        {
            original.Position = 0;
            Stream cloning = new MemoryStream();

            const int bufferSize = 1024;
            byte[] buffer = new byte[bufferSize];
            int readBytes;
            while ((readBytes = original.Read(buffer, 0, bufferSize)) > 0)
                cloning.Write(buffer, 0, readBytes);

            cloning.Position = 0;
            return cloning;
        }

        public void Initialize(Stream styleSheetStream, bool closeStream)
        {
            XmlReader styleSheetReader = null;
            try
            {
                styleSheetReader = XmlReader.Create(styleSheetStream);
                mXslTransformer = new XslCompiledTransform();
                mXslTransformer.Load(styleSheetReader);
            }
            finally
            {
                if (closeStream)
                    CloseStreamAndReader(styleSheetStream, styleSheetReader);
            }
        }

        private static void CloseStreamAndReader(Stream stream, XmlReader reader)
        {
            if (reader != null)
            {
                reader.Close();
            }
            stream.Close();
        }

        public void Transform(object xmlSerializableParameter, Stream outputStream)
        {
            if (mXslTransformer == null)
                throw new InvalidOperationException("You must first initialize the transformer before you can use it.");

            Stream serializationStream = SerializeObject(xmlSerializableParameter);
            XmlReader reader = XmlReader.Create(serializationStream);
            XmlWriter writer = XmlWriter.Create(outputStream);

            mXslTransformer.Transform(reader, writer);
        }

        private Stream SerializeObject(object parameter)
        {
            Stream serializationStream = new MemoryStream();
            XmlSerializer serializer = new XmlSerializer(parameter.GetType());
            serializer.Serialize(serializationStream, parameter);

            RaiseObjectSerializedEvent(serializationStream);

            serializationStream.Position = 0;
            return serializationStream;
        }
    }
}