C#实现MD5WITHRSA签名

 1 using System; 2 using System.Collections.Generic; 3 using System.Linq; 4 using System.Text; 5 using System.Security.Cryptography.X509Certificates; 6 using System.Security.Cryptography; 7  8 namespace md5WithRSATest 9 {10     public class MD5WithRSA11     {12         PRivate static char[] bcdLookup = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };13 14         /// <summary>15         /// 返回MD5WithRSA的签名字符串16         /// </summary>17         /// <param name="fileName">pfx证书文件的路径</param>18         /// <param name="passWord">pfx证书密码</param>19         /// <param name="strdata">待签名字符串</param>20         /// <param name="encoding">字符集,默认为ISO-8859-1</param>21         /// <returns>返回MD5WithRSA的签名字符串</returns>22         public static string SignData(string fileName, string password, string strdata, string encoding = "ISO-8859-1")23         {24             X509Certificate2 objx5092;25             if (string.IsNullOrWhiteSpace(password))26             {27                 objx5092 = new X509Certificate2(fileName);28             }else29             {30                 objx5092 = new X509Certificate2(fileName, password);31             }32             RSACryptoServiceProvider rsa = objx5092.PrivateKey as RSACryptoServiceProvider;33             byte[] data = Encoding.GetEncoding(encoding).GetBytes(strdata);34             byte[] hashvalue = rsa.SignData(data, "MD5");//为证书采用MD5withRSA 签名35             return bytesToHexStr(hashvalue);///将签名结果转化为16进制字符串36         }37         /// <summary>38         /// 将签名结果转化为16进制字符串39         /// </summary>40         /// <param name="bcd">签名结果的byte数字</param>41         /// <returns>16进制字符串</returns>42         private static string bytesToHexStr(byte[] bcd)43         {44             StringBuilder s = new StringBuilder(bcd.Length * 2);45             for (int i = 0; i < bcd.Length; i++)46             {47                 s.Append(bcdLookup[(bcd[i] >> 4) & 0x0f]);48                 s.Append(bcdLookup[bcd[i] & 0x0f]);49             }50             return s.ToString();51         }52     }53 }