C#实现MD5WITHRSA签名

这是很久以前的写的一篇博客了,今天把他重新找出来整理一下发布到博客园

当时对接银联的时候搞了很久都没搞出来,后来一个偶然的机会发现类似的一个代码参考了一下终于弄好了

这段代码主要是实现了C#服务端对接手机银联的java端的接口的签名

希望可以帮到大家

 using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Text;
 using System.Security.Cryptography.X509Certificates;
 using System.Security.Cryptography;

 namespace MD5WithRSATest
 {
     public class MD5WithRSA
     {
         private static char[] bcdLookup = { '', '', '', '', '', '', '', '', '', '', 'a', 'b', 'c', 'd', 'e', 'f' };

         /// <summary>
         /// 返回MD5WithRSA的签名字符串
         /// </summary>
         /// <param name="fileName">pfx证书文件的路径</param>
         /// <param name="password">pfx证书密码</param>
         /// <param name="strdata">待签名字符串</param>
         /// <param name="encoding">字符集,默认为ISO-8859-1</param>
         /// <returns>返回MD5WithRSA的签名字符串</returns>
         public static string SignData(string fileName, string password, string strdata, string encoding = "ISO-8859-1")
         {
             X509Certificate2 objx5092;
             if (string.IsNullOrWhiteSpace(password))
             {
                 objx5092 = new X509Certificate2(fileName);
             }else
             {
                 objx5092 = new X509Certificate2(fileName, password);
             }
             RSACryptoServiceProvider rsa = objx5092.PrivateKey as RSACryptoServiceProvider;
             byte[] data = Encoding.GetEncoding(encoding).GetBytes(strdata);
             byte[] hashvalue = rsa.SignData(data, "MD5");//为证书采用MD5withRSA 签名
             return bytesToHexStr(hashvalue);///将签名结果转化为16进制字符串
         }
         /// <summary>
         /// 将签名结果转化为16进制字符串
         /// </summary>
         /// <param name="bcd">签名结果的byte数字</param>
         /// <returns>16进制字符串</returns>
         private static string bytesToHexStr(byte[] bcd)
         {
             StringBuilder s = new StringBuilder(bcd.Length * );
             for (int i = ; i < bcd.Length; i++)
             {
                 s.Append(bcdLookup[(bcd[i] >> ) & 0x0f]);
                 s.Append(bcdLookup[bcd[i] & 0x0f]);
             }
             return s.ToString();
         }
     }
 }