http://www.codeproject.com/KB/files/encryption.aspx
/**////<summary>
/// Steve Lydford - 12/05/2008. /// /// Encrypts a file using Rijndael algorithm. ///</summary> ///<param name="inputFile"></param>
///<param name="outputFile"></param>
private void EncryptFile(string inputFile, string outputFile) ...{ try
...{ string password = @"myKey123"; // Your Key Here UnicodeEncoding UE = new UnicodeEncoding(); byte[] key = UE.GetBytes(password); string cryptFile = outputFile; FileStream fsCrypt = new FileStream(cryptFile, FileMode.Create); RijndaelManaged RMCrypto = new RijndaelManaged(); CryptoStream cs = new CryptoStream(fsCrypt, RMCrypto.CreateEncryptor(key, key), CryptoStreamMode.Write); FileStream fsIn = new FileStream(inputFile, FileMode.Open); int data; while ((data = fsIn.ReadByte()) != -1) cs.WriteByte((byte)data); fsIn.Close(); cs.Close(); fsCrypt.Close();
} catch ...{ MessageBox.Show("Encryption failed!", "Error"); } } /**////<summary> /// Steve Lydford - 12/05/2008. /// /// Decrypts a file using Rijndael algorithm. ///</summary> ///<param name="inputFile"></param> ///<param name="outputFile"></param> private void DecryptFile(string inputFile, string outputFile) ...{ ...{ string password = @"myKey123"; // Your Key Here UnicodeEncoding UE = new UnicodeEncoding(); byte[] key = UE.GetBytes(password); FileStream fsCrypt = new FileStream(inputFile, FileMode.Open); RijndaelManaged RMCrypto = new RijndaelManaged(); CryptoStream cs = new CryptoStream(fsCrypt, RMCrypto.CreateDecryptor(key, key), CryptoStreamMode.Read); FileStream fsOut = new FileStream(outputFile, FileMode.Create); int data; while ((data = cs.ReadByte()) != -1) fsOut.WriteByte((byte)data); fsOut.Close(); cs.Close(); fsCrypt.Close(); } }