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我有一个小应用程序，它可以读取任何文件（即 .exe、.jpg、.img 和所有其他文件），将其传输到bytes[]trough File.ReadAllBytes()，使用 3DES 加密并使用File.WriteAllBytes(). 比有做同样反向的解密方法。我的问题是，在 300MB 的原始文件中一切正常，而不是内存不足异常。任何建议如何解决这个问题？如何处理大于 1GB 的文件？它可以帮助使用streamreader或cryptostream reader和writer吗？

读取和加密文件：

 try
 {
     saveFileDialog1.FileName = "";
     DialogResult result = openFileDialog1.ShowDialog();
     if (result == DialogResult.OK) 
     {
         byte[] Results;
         System.Text.UTF8Encoding UTF8 = new System.Text.UTF8Encoding();
         fileToEncrypt = File.ReadAllBytes(openFileDialog1.FileName);
         MD5CryptoServiceProvider HashProvider = new MD5CryptoServiceProvider();
         byte[] TDESKey = HashProvider.ComputeHash(UTF8.GetBytes(textBox1.Text));
         TripleDESCryptoServiceProvider TDESAlgorithm = new TripleDESCryptoServiceProvider();
         TDESAlgorithm.Key = TDESKey;
         TDESAlgorithm.Mode = CipherMode.ECB;
         TDESAlgorithm.Padding = PaddingMode.PKCS7;
         ICryptoTransform Encryptor = TDESAlgorithm.CreateEncryptor();
         Results = Encryptor.TransformFinalBlock(fileToEncrypt, 0, fileToEncrypt.Length);
         saveFileDialog1.FileName = openFileDialog1.SafeFileName;
         saveFileDialog1.ShowDialog();
         if (saveFileDialog1.FileName != "")
         {
             File.WriteAllBytes(saveFileDialog1.FileName, Results);
         }
         TDESAlgorithm.Clear();
         HashProvider.Clear();
     }
 }
 catch
 {
     MessageBox.Show("Your system has not enough memory.", "", MessageBoxButtons.OK, MessageBoxIcon.Error);
 }

解密和保存：

 try
 {
     openFileDialog1.FileName = "";
     DialogResult result = openFileDialog1.ShowDialog();
     if (result == DialogResult.OK) // Test result.
     {
         byte[] Results;
         System.Text.UTF8Encoding UTF8 = new System.Text.UTF8Encoding();
         fileToDecrypt = File.ReadAllBytes(openFileDialog1.FileName);
         MD5CryptoServiceProvider HashProvider = new MD5CryptoServiceProvider();
         byte[] TDESKey = HashProvider.ComputeHash(UTF8.GetBytes(textBox1.Text));
         TripleDESCryptoServiceProvider TDESAlgorithm = new TripleDESCryptoServiceProvider();
         TDESAlgorithm.Key = TDESKey;
         TDESAlgorithm.Mode = CipherMode.ECB;
         TDESAlgorithm.Padding = PaddingMode.PKCS7;
         ICryptoTransform Decryptor = TDESAlgorithm.CreateDecryptor();
         Results = Decryptor.TransformFinalBlock(fileToDecrypt, 0, fileToDecrypt.Length);
         saveFileDialog1.FileName = Path.GetFileName(openFileDialog1.FileName);
         saveFileDialog1.ShowDialog();
         if (saveFileDialog1.FileName != "")
         {
             File.WriteAllBytes(saveFileDialog1.FileName, Results);
         }
         TDESAlgorithm.Clear();
         HashProvider.Clear();
     }
 }
 catch 
 {
     MessageBox.Show("Master password is wrong", "", MessageBoxButtons.OK, MessageBoxIcon.Error);
 }

我只是业余爱好编码器，所以我祈祷我的代码有一些仁慈:)

textbox1.Text是主密码。

4

1 回答 1

0

最后我有一些使用cryptostream的东西-在我的笔记本上8分钟加密2,7GB文件。感谢马格努斯的努力，我也会试试你的代码

加密方法

DialogResult result = openFileDialog1.ShowDialog();
        if (result == DialogResult.OK) 
        {
            saveFileDialog1.FileName = openFileDialog1.SafeFileName;
            saveFileDialog1.ShowDialog();
            FileStream readFile = new FileStream(openFileDialog1.FileName, FileMode.Open, FileAccess.Read);
            FileStream writeFile = new FileStream(saveFileDialog1.FileName, FileMode.OpenOrCreate, FileAccess.Write);
            writeFile.SetLength(0);

            byte[] storage = new byte[100];
            long fileWritten = 0;
            long totlen = readFile.Length;
            int bytesToWrite;

            System.Text.UTF8Encoding UTF8 = new System.Text.UTF8Encoding();
            MD5CryptoServiceProvider HashProvider = new MD5CryptoServiceProvider();
            byte[] TDESKey = HashProvider.ComputeHash(UTF8.GetBytes(textBox1.Text));
            TripleDESCryptoServiceProvider TDES = new TripleDESCryptoServiceProvider();
            TDES.Key = TDESKey;
            TDES.Mode = CipherMode.ECB;
            TDES.Padding = PaddingMode.PKCS7;
            CryptoStream cryptStream = new CryptoStream(writeFile, TDES.CreateEncryptor(), CryptoStreamMode.Write);
            while (fileWritten < totlen)
            {
                bytesToWrite = readFile.Read(storage, 0, 100);
                cryptStream.Write(storage, 0, bytesToWrite);
                fileWritten = fileWritten + bytesToWrite;

            }

            cryptStream.Close();
            TDES.Clear();
            HashProvider.Clear();
        }

解密方法与使用 TDES.CreateDecryptor()相反 TDES.CreateEncryptor()。我必须说File.ReadAllBytes()，File.WriteAllBytes()文件 300MB 大小比流快得多。

于 2012-05-08T01:26:40.070 回答