加密：  调用时： Encrypt_DES16(“2AF349243535BCD3”, "1111111111111111");

 public static string Encrypt_DES16(string str_in_data, string str_DES_KEY) //数据为十六进制
        {
            try
            {
                byte[] shuju = new byte[8];
                byte[] keys = new byte[8];
                for (int i = 0; i < 8; i++)
                {
                    shuju[i] = Convert.ToByte(str_in_data.Substring(i * 2, 2), 16);
                    keys[i] = Convert.ToByte(str_DES_KEY.Substring(i * 2, 2), 16);
                }
                DES desEncrypt = new DESCryptoServiceProvider();
                desEncrypt.Mode = CipherMode.ECB;
                //desEncrypt.Key = ASCIIEncoding.ASCII.GetBytes(str_DES_KEY);
                desEncrypt.Key = keys;
                byte[] Buffer;
                Buffer = shuju;//ASCIIEncoding.ASCII.GetBytes(str_in_data);
                ICryptoTransform transForm = desEncrypt.CreateEncryptor();
                byte[] R;
                R = transForm.TransformFinalBlock(Buffer, 0, Buffer.Length);
                string return_str = "";
                foreach (byte b in R)
                {
                    return_str += b.ToString("X2");
                }
                return_str = return_str.Substring(0, 16);
                return return_str;
            }
            catch (Exception e)
            {
                throw e;
            }
        }

解密：调用时： Encrypt_DES16(“C47EC89B0A247A47”, "1111111111111111");

 //DES解密
        public static string Decrypt_DES16(string str_in_data, string str_DES_KEY)//数据和密钥为十六进制
        {
            byte[] shuju = new byte[8];
            byte[] keys = new byte[8];
            for (int i = 0; i < 8; i++)
            {
                shuju[i] = Convert.ToByte(str_in_data.Substring(i * 2, 2), 16);
                keys[i] = Convert.ToByte(str_DES_KEY.Substring(i * 2, 2), 16);
            }
            DES desDecrypt = new DESCryptoServiceProvider();
            desDecrypt.Mode = CipherMode.ECB;
            desDecrypt.Key = keys;
            desDecrypt.Padding = System.Security.Cryptography.PaddingMode.None;
            byte[] Buffer = shuju;
            ICryptoTransform transForm = desDecrypt.CreateDecryptor();
            byte[] R;
            R = transForm.TransformFinalBlock(Buffer, 0, Buffer.Length);
            string return_str = "";
            foreach (byte b in R)
            {
                return_str += b.ToString("X2");
            }
            return return_str;
        }