C# RSA加密解密 簽名實現

    class RSACryptoItem
    {
        public RSACryptoServiceProvider Provider;
        public List<byte> PubKeyBytes;
    }

    public class RSAManager
    {
        private RSACryptoItem item;

        public RSAManager()
        {
            item = GenRSACryptoItem();
        }

        private RSACryptoItem GenRSACryptoItem()
        {
            RSACryptoServiceProvider provider = new RSACryptoServiceProvider();
            List<byte> pubKeyBytes = new List<byte>(provider.ExportCspBlob(false));
            return new RSACryptoItem
            {
                Provider = provider,
                PubKeyBytes = pubKeyBytes,
            };
        }

        /// <summary>
        /// 使用公鑰加密
        /// </summary>
        /// <param name="inBytes"></param>
        /// <param name="publicKey"></param>
        /// <returns></returns>
        public static byte[] EncryptDataByPublicKey(byte[] inBytes, string publicKey)
        {
            RSACryptoServiceProvider provider = new RSACryptoServiceProvider();
            provider.FromXmlString(publicKey);
            return provider.Encrypt(inBytes, false);
        }

        /// <summary>
        /// 使用私鑰解密
        /// </summary>
        /// <param name="inBytes"></param>
        /// <param name="privateKey"></param>
        /// <returns></returns>
        public static byte[] DecryptDataByPrivateKey(byte[] inBytes,string privateKey)
        {
            RSACryptoServiceProvider provider = new RSACryptoServiceProvider();
            provider.FromXmlString(privateKey);
            return provider.Decrypt(inBytes, false);
        }


        /// <summary>
        /// 生成數字簽名
        /// </summary>
        /// <param name="originalText">原文</param>
        /// <param name="privateKey"></param>
        /// <returns></returns>
        public static string GenSign(string originalText,string privateKey)
        {
            byte[] byteData = Encoding.UTF8.GetBytes(originalText);
            RSACryptoServiceProvider provider = new RSACryptoServiceProvider();
            provider.FromXmlString(privateKey);
            //使用SHA1進行摘要算法，生成簽名
            byteData = provider.SignData(byteData, new SHA1CryptoServiceProvider());
            return Convert.ToBase64String(byteData);
        }

        /// <summary>
        /// 驗證簽名
        /// </summary>
        /// <param name="originalText">原文</param>
        /// <param name="SignedData">簽名</param>
        /// <param name="publicKey">公鑰</param>
        /// <returns></returns>
        public static bool VerifySigned(string originalText, string signedData, string publicKey)
        {
            RSACryptoServiceProvider provider = new RSACryptoServiceProvider();
            provider.FromXmlString(publicKey);
            byte[] byteData = Encoding.UTF8.GetBytes(originalText);
            byte[] signData = Convert.FromBase64String(signedData);
            return provider.VerifyData(byteData, new SHA1CryptoServiceProvider(), signData);
        }

        public byte[] EncryptData(byte[] inBytes)
        {
            if (item != null)
                return item.Provider.Encrypt(inBytes, false);
            return null;
        }

        public byte[] DecryptData(byte[] inBytes)
        {
            if (item != null)
                return item.Provider.Decrypt(inBytes,false);
            return null;
        }
    }

使用例子：
static void Main(string[] args)
        {
            //rsa使用方法1
            //RSAManager rsaManager = new RSAManager();
            string str = "hello world!!!";
            //byte[] encryptStr = rsaManager.EncryptData(Encoding.UTF8.GetBytes(str));
            //Console.WriteLine("Encrypt Data:");
            //foreach (var b in encryptStr)
            //{
            //    Console.Write(b);
            //}
            //Console.WriteLine();
            //Console.WriteLine("Decrypt Data:");
            //Console.WriteLine(Encoding.UTF8.GetString(rsaManager.DecryptData(encryptStr)));

            //rsa使用方法2
            //RSACryptoServiceProvider provider = new RSACryptoServiceProvider();
            //string publicKey = provider.ToXmlString(false);
            //string privateKey = provider.ToXmlString(true);
            //byte[] encryptStr = RSAManager.EncryptDataByPublicKey(Encoding.UTF8.GetBytes(str), publicKey);
            //Console.WriteLine("Encrypt Data:");
            //foreach (var b in encryptStr)
            //{
            //    Console.Write(b);
            //}
            //Console.WriteLine();
            //Console.WriteLine("Decrypt Data:");
            //Console.WriteLine(Encoding.UTF8.GetString(RSAManager.DecryptDataByPrivateKey(encryptStr,privateKey)));


            //使用數字簽名
            RSACryptoServiceProvider provider = new RSACryptoServiceProvider();
            string publicKey = provider.ToXmlString(false);
            string privateKey = provider.ToXmlString(true);
            string originalText = "hello world!!!";
            string signStr = RSAManager.GenSign(originalText, privateKey);
            Console.WriteLine("sign:\r\n" + signStr +"\r\n");
            //Console.WriteLine($"VerifySigned:\r\n{RSAManager.VerifySigned(originalText, signStr, publicKey)}");
            Console.WriteLine($"VerifySigned:\r\n{RSAManager.VerifySigned("error string code", signStr, publicKey)}");

            Console.ReadKey();
        }