static void Main(string[] args)
        {
            try
            {
                //創建一個編碼實例用來將字符串轉換成byte數組
                UnicodeEncoding ByteConverter = new UnicodeEncoding();

                //Create byte arrays to hold original, encrypted, and decrypted data.
                byte[] dataToEncrypt = ByteConverter.GetBytes("
 
Data to Encrypt");
                byte[] encryptedData;
                byte[] decryptedData;
                using (RSACryptoServiceProvider RSA = new RSACryptoServiceProvider())
                {
                    encryptedData = RSAEncrypt(dataToEncrypt, RSA.ExportParameters(false), false);
                    decryptedData 
 
= RSADecrypt(encryptedData, RSA.ExportParameters(true), false);
                    Console.WriteLine("Decrypted plaintext: {0}", ByteConverter.GetString(decryptedData));
                }
            }
            catch (ArgumentNullException)
            {
                Console.WriteLine("Encryption failed.
 
");

            }
            Console.Read();
        }

        static public byte[] RSAEncrypt(byte[] DataToEncrypt, RSAParameters RSAKeyInfo, bool DoOAEPPadding)
        {
            try
            {
                byte[] encryptedData;
                //創建一個RSACryptoServiceProvider實例.
                using (RSACryptoServiceProvider RSA = new RSACryptoServiceProvider())
                {

                    //指定共有鑰匙
                    RSA.ImportParameters(RSAKeyInfo);
                    //加密,並且指定是否運行在XP更高的版本中
                    encryptedData = RSA.Encrypt(DataToEncrypt, DoOAEPPadding);
                }
                return encryptedData;
            }
            catch (CryptographicException e)
            {
                Console.WriteLine(e.Message);

                return null;
            }

        }

        static public byte[] RSADecrypt(byte[] DataToDecrypt, RSAParameters RSAKeyInfo, bool DoOAEPPadding)
        {
            try
            {
                byte[] decryptedData;
                using (RSACryptoServiceProvider RSA = new RSACryptoServiceProvider())
                {
                    RSA.ImportParameters(RSAKeyInfo);
                    decryptedData = RSA.Decrypt(DataToDecrypt, DoOAEPPadding);
                }
                return decryptedData;
            }
            //Catch and display a CryptographicException  
            //to the console.
            catch (CryptographicException e)
            {
                Console.WriteLine(e.ToString());

                return null;
            }

        }

C#中RSA的簡單使用