C#读取cer证书获取秘钥给字符串加密(RSA)

         /// <summary>
         /// 使用私钥加密字符串
         /// </summary>
         /// <param name="key">需加密的字符</param>
         /// <param name="keyPath">私钥证书文件地址</param>
         public string EncryptKey(string key,string keyPath)
        {
            X509Certificate2 c2 = new X509Certificate2(AppDomain.CurrentDomain.BaseDirectory + "bin\\client.cer");
  
            string keyPublic2 = c2.PublicKey.Key.ToXmlString(false);

            string cypher2 = RSAEncrypt(keyPublic2, key);  // 加密  
            return cypher2;
         }  

       
        /// <summary>
        /// RSA解密
        /// </summary>
        /// <param name="xmlPrivateKey"></param>
        /// <param name="m_strDecryptString"></param>
        /// <returns></returns>
        static string RSADecrypt(string xmlPrivateKey, string m_strDecryptString)
        {
            RSACryptoServiceProvider provider = new RSACryptoServiceProvider();
            provider.FromXmlString(xmlPrivateKey);
            byte[] rgb = Convert.FromBase64String(m_strDecryptString);
            byte[] bytes = provider.Decrypt(rgb, false);
            return new UnicodeEncoding().GetString(bytes);
        }
        /// <summary>   
        /// RSA加密   
        /// </summary>   
        /// <param name="xmlPublicKey"></param>   
        /// <param name="m_strEncryptString"></param>   
        /// <returns></returns>   
        static string RSAEncrypt(string xmlPublicKey, string m_strEncryptString)
        {
            RSACryptoServiceProvider provider = new RSACryptoServiceProvider();
            provider.FromXmlString(xmlPublicKey);
            byte[] bytes = new UnicodeEncoding().GetBytes(m_strEncryptString);
            return Convert.ToBase64String(provider.Encrypt(bytes, false));
        }