添加C#sdk

sop-sdk/sdk-csharp/SDKCSharp/Utility/RSAUtil.cs

@@ -0,0 +1,47 @@
+using System;
+using System.Xml;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Security.Cryptography;
+using System.Text;
+
+using Org.BouncyCastle.Asn1.Pkcs;
+using Org.BouncyCastle.Asn1.X509;
+using Org.BouncyCastle.Crypto.Generators;
+using Org.BouncyCastle.Crypto.Parameters;
+using Org.BouncyCastle.Math;
+using Org.BouncyCastle.Pkcs;
+using Org.BouncyCastle.Security;
+using Org.BouncyCastle.Crypto.Engines;
+using Org.BouncyCastle.X509;
+using Org.BouncyCastle.Crypto;
+using Org.BouncyCastle.Asn1;
+using Org.BouncyCastle.Crypto.Encodings;
+
+namespace SDKCSharp.Utility
+{
+    public class RSAUtil
+    {
+
+        static Encoding UTF8 = Encoding.UTF8;
+        static RSA rsa = new RSA();
+
+        /// <summary>
+        /// 私钥加密
+        /// </summary>
+        /// <returns>The by private key.</returns>
+        /// <param name="data">内容.</param>
+        /// <param name="privateKey">私钥.</param>
+        public static string EncryptByPrivateKey(string data, string privateKey)
+        {
+            return rsa.EncryptByPrivateKey(data, privateKey);
+        }
+
+
+    }
+
+
+
+
+}