base64 encoding Problems **SOLVED**

[Sgt-Peppa]

Hey all, heres a short description of what I do.

I have an xml document. Structure and size do not matter here.
Important, it is UTF-8 encoded.

So, what I do now is take that whole xmlDocument get the OuterXml of it, and do a base64encoding of the whole document.

That base64 String is now being put into another xmldocument.

Everything works fine, up till now,
but what I do next is to decode that data again, select the base64 data from the document and save it again. That works to, but if I now open the latest xml Document it is UTF-16 encoded all the sudden.

What am I doing wrong?

Heres my Source for encoding the data:

using System;
using System.Xml;
using System.IO;
using System.Text;

namespace base64EncodeData
{
	/// <summary>
	/// Summary description for Class1.
	/// </summary>
	class Class1
	{
		/// <summary>
		/// The main entry point for the application.
		/// </summary>
		[STAThread]
		static void Main(string[] args)
		{
			StringBuilder myBuilder = new StringBuilder();
			myBuilder.Append("<?xml version='1.0'?>");
			myBuilder.Append("<root>");
			myBuilder.Append("<data>");
			myBuilder.Append("</data>");
			myBuilder.Append("</root>");
			
			StreamReader myReader = new StreamReader("test.xml");
			string workingData = myReader.ReadToEnd();
			myReader.Close();

			byte[] encData_byte = new byte[workingData.Length];
			encData_byte = System.Text.Encoding.Unicode.GetBytes(workingData);	
			string encodedData = Convert.ToBase64String(encData_byte);

			XmlDocument myDoc = new XmlDocument();
			myDoc.LoadXml(myBuilder.ToString());
			myDoc.DocumentElement.SelectSingleNode("//data").InnerText = encodedData;

			StreamWriter myWriter = new StreamWriter(Guid.NewGuid().ToString() + ".xml");
			myWriter.Write(myDoc.DocumentElement.OuterXml);
			myWriter.Flush();
			myWriter.Close();
		}
	}
}

Heres my Source for decoding the data:

using System;
using System.Xml;
using System.IO;

namespace base64DecodeData
{
	/// <summary>
	/// Summary description for Class1.
	/// </summary>
	class Class1
	{
		/// <summary>
		/// The main entry point for the application.
		/// </summary>
		[STAThread]
		static void Main(string[] args)
		{
			Console.WriteLine("Beginning of decoding");
			Console.WriteLine("Load Document");
			XmlDocument myDoc = new XmlDocument();
			myDoc.Load(args[0]);
			string data = myDoc.DocumentElement.SelectSingleNode("//data").InnerText.ToString();
			Console.WriteLine("Decode Data");
			System.Text.UTF8Encoding encoder = new System.Text.UTF8Encoding();	
			System.Text.Decoder utf8Decode = encoder.GetDecoder();
			byte[] todecode_byte = Convert.FromBase64String(data);
			int charCount = utf8Decode.GetCharCount(todecode_byte, 0, todecode_byte.Length);	
			char[] decoded_char = new char[charCount];
			utf8Decode.GetChars(todecode_byte, 0, todecode_byte.Length, decoded_char, 0);					
			string result = new String(decoded_char);
			Console.WriteLine("Save Document");
			StreamWriter myWriter = new StreamWriter(Guid.NewGuid().ToString() + ".xml");
			myWriter.Write(result);
			myWriter.Flush();
			myWriter.Close();
			Console.WriteLine("End of Decoding");
		}
	}
}

Heres what my XmlDocument that I start with looks like in UltraEdit:

<?xml version="1.0"?>
<root>
	<testdata>alottadata</testdata>
</root>

And here it is after doing the encoding-decoding process

Wheres my Error? Any help is appreciated
Thanks,

Stephan