【RSA加密】PEM格式密钥转换成XML格式（方法一）

Nuget首先需要添加引用：Portable.BouncyCastle

        /// <summary>    
        /// PEM格式公钥转换成XML格式公钥
        /// </summary>    
        /// <param name="publicKey">PEM格式公钥，（纯文字字符，注意不带-----BEGIN PUBLIC KEY-----和-----END PUBLIC KEY-----）</param>
        /// <returns>转换后的XML格式公钥</returns>    
        public static string RSAPublicKeyXML(string publicKey)
        {
            RsaKeyParameters publicKeyParam = (RsaKeyParameters)PublicKeyFactory.CreateKey(Convert.FromBase64String(publicKey));

            return string.Format("<RSAKeyValue><Modulus>{0}</Modulus><Exponent>{1}</Exponent></RSAKeyValue>",
                    Convert.ToBase64String(publicKeyParam.Modulus.ToByteArrayUnsigned()),
                    Convert.ToBase64String(publicKeyParam.Exponent.ToByteArrayUnsigned()));
        }

        /// <summary>  
        /// PEM格式私钥转换成XML格式私钥
        /// </summary>  
        /// <param name="privateKey">PEM格式私钥，（纯文字字符，注意不带-----BEGIN PRIVATE KEY-----和-----END PRIVATE KEY-----）</param>  
        /// <returns></returns>  
        public static string RSAPrivateKeyToXml(string privateKey)
        {
            RsaPrivateCrtKeyParameters privateKeyParam = (RsaPrivateCrtKeyParameters)PrivateKeyFactory.CreateKey(Convert.FromBase64String(privateKey));

            return string.Format("<RSAKeyValue><Modulus>{0}</Modulus><Exponent>{1}</Exponent><P>{2}</P><Q>{3}</Q><DP>{4}</DP><DQ>{5}</DQ><InverseQ>{6}</InverseQ><D>{7}</D></RSAKeyValue>",
                Convert.ToBase64String(privateKeyParam.Modulus.ToByteArrayUnsigned()),
                Convert.ToBase64String(privateKeyParam.PublicExponent.ToByteArrayUnsigned()),
                Convert.ToBase64String(privateKeyParam.P.ToByteArrayUnsigned()),
                Convert.ToBase64String(privateKeyParam.Q.ToByteArrayUnsigned()),
                Convert.ToBase64String(privateKeyParam.DP.ToByteArrayUnsigned()),
                Convert.ToBase64String(privateKeyParam.DQ.ToByteArrayUnsigned()),
                Convert.ToBase64String(privateKeyParam.QInv.ToByteArrayUnsigned()),
                Convert.ToBase64String(privateKeyParam.Exponent.ToByteArrayUnsigned()));
        }