请问哪位大虾有C#实现的Rijndael算法的源程序？

using System; 
using System.IO; 
using System.Security.Cryptography; class CryptoEx 
{ 
public static void Main(string[] args) 
{ 
if (args.Length!=1) 
{ 
Console.WriteLine("FileName Not Entered. Specify a filename to encrypt."); 
return; 
} string file = args[0]; 
string tempfile = Path.GetTempFileName(); 
// Open the file to readFileStream fsIn = File.Open(file,FileMode.Open,FileAccess.Read); 
FileStream fsOut = File.Open(tempfile, FileMode.Open,FileAccess.Write); SymmetricAlgorithm symm = new RijndaelManaged(); //creating an instance
ICryptoTransform transform = symm.CreateEncryptor(); //and calling the CreateEncryptor method which //creates a symmetric encryptor object.
CryptoStream cstream = new CryptoStream(fsOut,transform,CryptoStreamMode.Write); BinaryReader br = new BinaryReader(fsIn); cstream.Write(br.ReadBytes((int)fsIn.Length),0,(int)fsIn.Length); cstream.FlushFinalBlock(); 
cstream.Close(); 
fsIn.Close(); 
fsOut.Close(); Console.WriteLine("Created Encrypted File {0}", tempfile); fsIn = File.Open(tempfile,FileMode.Open,FileAccess.Read); 
transform = symm.CreateDecryptor(); 
cstream = new CryptoStream(fsIn,transform,CryptoStreamMode.Read); StreamReader sr = new StreamReader(cstream); 
Console.WriteLine("Decrypted the File: " + sr.ReadToEnd()); 
fsIn.Close(); 
}