代码如下:
SymmetricMethod类中有如下方法:
         /// <summary>   
        /// 解密方法   
        /// </summary>   
        /// <param name="Source">待解密的串</param>   
        /// <returns>经过解密的串</returns>   
        public string Decrypto(string Source)
        {
            byte[] bytIn = Convert.FromBase64String(Source);
            MemoryStream ms = new MemoryStream(bytIn, 0, bytIn.Length);
            mobjCryptoService.Key = GetLegalKey();
            mobjCryptoService.IV = GetLegalIV();
            ICryptoTransform encrypto = mobjCryptoService.CreateDecryptor();
            CryptoStream cs = new CryptoStream(ms, encrypto, CryptoStreamMode.Read);
            StreamReader sr = new StreamReader(cs);
            return sr.ReadToEnd();此处报错。
        }
在窗口中如下使用:
SymmetricMethod sm = new SymmetricMethod();
string ifActiveation = SystemConfig.GetConfigData("Activeation", string.Empty);//此处得到的ifActiveation为“”
            if (sm.Decrypto(ifActiveation).Length != 1)
            {
                MessageBox.Show("您的软件未激活,请先激活软件..........");
                tabLogin.SelectedIndex = 2;
            }

解决方案 »

  1.   

    你的密钥呢?实在不行,用下面的这个:
            private static byte[] Keys = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };
            /// <summary>
            /// DES加密字符串
            /// </summary>
            /// <param name="encryptString">待加密的字符串</param>
            /// <param name="encryptKey">加密密钥,要求为8位</param>
            /// <returns>加密成功返回加密后的字符串,失败返回源串</returns>
            public static string Encrypt(string encryptString, string encryptKey)
            {
                try
                {
                    byte[] rgbKey = Encoding.UTF8.GetBytes(encryptKey.Substring(0, 8));
                    byte[] rgbIV = Keys;
                    byte[] inputByteArray = Encoding.UTF8.GetBytes(encryptString);
                    DESCryptoServiceProvider dCSP = new DESCryptoServiceProvider();
                    MemoryStream mStream = new MemoryStream();
                    CryptoStream cStream = new CryptoStream(mStream, dCSP.CreateEncryptor(rgbKey, rgbIV), CryptoStreamMode.Write);
                    cStream.Write(inputByteArray, 0, inputByteArray.Length);
                    cStream.FlushFinalBlock();
                    return Convert.ToBase64String(mStream.ToArray());
                }
                catch
                {
                    return encryptString;
                }
            }        /// <summary>
            /// DES解密字符串
            /// </summary>
            /// <param name="decryptString">待解密的字符串</param>
            /// <param name="decryptKey">解密密钥,要求为8位,和加密密钥相同</param>
            /// <returns>解密成功返回解密后的字符串,失败返源串</returns>
            public static string Decrypt(string decryptString, string decryptKey)
            {
                try
                {
                    byte[] rgbKey = Encoding.UTF8.GetBytes(decryptKey);
                    byte[] rgbIV = Keys;
                    byte[] inputByteArray = Convert.FromBase64String(decryptString);
                    DESCryptoServiceProvider DCSP = new DESCryptoServiceProvider();
                    MemoryStream mStream = new MemoryStream();
                    CryptoStream cStream = new CryptoStream(mStream, DCSP.CreateDecryptor(rgbKey, rgbIV), CryptoStreamMode.Write);
                    cStream.Write(inputByteArray, 0, inputByteArray.Length);
                    cStream.FlushFinalBlock();
                    return Encoding.UTF8.GetString(mStream.ToArray());
                }
                catch
                {
                    return decryptString;
                }
            }
      

  2.   

    string ifActiveation = SystemConfig.GetConfigData("Activeation", string.Empty);//此处得到的ifActiveation为“” 
    你这一句就已经表明你读到的数据位空
    请检查GetConfigData函数的实现
      

  3.   


    现在做的是共享软件,软件没有注册前SystemConfig.GetConfigData("Activeation", string.Empty)得到的就是空字符串啊!
      

  4.   


    //应该在外面加一个判断
    if(ifActiveation.Trim()!="")
    {
    if (sm.Decrypto(ifActiveation).Length != 1) 
                { 
                    MessageBox.Show("您的软件未激活,请先激活软件.........."); 
                    tabLogin.SelectedIndex = 2; 
                } 
    }