checksn.cs

ASP.NET构建的笑傲江湖社区(C#,全源码提供)

using System;
using System.Security;
using System.Security.Cryptography;
using System.Diagnostics;
using System.Text;

namespace xajh
{
	/// <summary>
	/// CheckSN 的摘要说明。
	/// </summary>
	public class CheckSN
	{
		public string Decrypt3DES(string a_strString)
		{
			TripleDESCryptoServiceProvider DES = new TripleDESCryptoServiceProvider();
			MD5CryptoServiceProvider hashMD5 = new MD5CryptoServiceProvider();
			DES.Key = hashMD5.ComputeHash(ASCIIEncoding.ASCII.GetBytes("I#Love&fAnyuN1314^##("));
			DES.Mode = CipherMode.ECB;
			ICryptoTransform DESDecrypt = DES.CreateDecryptor();
			string result = "";
			try
			{
				byte[] Buffer = Convert.FromBase64String(a_strString);
				result = ASCIIEncoding.ASCII.GetString(DESDecrypt.TransformFinalBlock(Buffer, 0, Buffer.Length));
			}
			catch
			{
				result = "无效的认证码";
			}
			return result ;
		}
	}
}