Secret Key Cryptography: DES : DES « Security « C# / CSharp Tutorial

1. C# / CSharp Tutorial
2. Security
3. DES

using System;
using System.IO;
using System.Text;
using System.Security.Cryptography;

  class Class1
  {
    static void Main(string[] args)
    {
      byte[] bin = new byte[100]; 
      FileStream fsIn = new FileStream("input.txt", FileMode.Open, FileAccess.Read);

      long rdLen = 0;
      long totLen = fsIn.Length;
      int len;
            DESCryptoServiceProvider des = new DESCryptoServiceProvider();
      des.GenerateKey();
      des.GenerateIV();
      FileStream fsOut_DES = new FileStream("outputDES.txt", FileMode.Create, FileAccess.Write);
      CryptoStream desStream = new CryptoStream( fsOut_DES, 
        des.CreateEncryptor( des.Key, des.IV ), CryptoStreamMode.Write);

      while ( rdLen < totLen )
      {
        len = fsIn.Read(bin, 0, 100);
        System.Diagnostics.Debug.WriteLine("Read " + len.ToString() + " bytes.");
        desStream.Write(bin, 0, len );
        
        rdLen += len;
        Console.WriteLine("{0} Bytes Read.", rdLen );
      }

      desStream.Close();
      fsOut_DES.Close();
      fsIn.Close();
    }
  }