Question

我在我的应用程序中使用此代码加密和解密数据但代码使用文件流来完成所有工作这是代码：

    Dim bytKey As Byte()
    Dim bytIV As Byte()
    bytKey = CreateKey("mrbrashad1999")
    bytIV = CreateIV("mrbrashad1999")

    Try 'In case of errors.

        'Setup file streams to handle input and output.
        fsInput = New System.IO.FileStream(strInputFile, FileMode.Open, _
                                           FileAccess.Read)
        fsOutput = New System.IO.FileStream(strOutputFile, FileMode.OpenOrCreate, _
                                            FileAccess.Write)
        fsOutput.SetLength(0) 'make sure fsOutput is empty

        'Declare variables for encrypt/decrypt process.
        Dim bytBuffer(4096) As Byte 'holds a block of bytes for processing
        Dim lngBytesProcessed As Long = 0 'running count of bytes processed
        Dim lngFileLength As Long = fsInput.Length 'the input file's length
        Dim intBytesInCurrentBlock As Integer 'current bytes being processed
        Dim csCryptoStream As CryptoStream
        'Declare your CryptoServiceProvider.
        Dim cspRijndael As New System.Security.Cryptography.RijndaelManaged
        'Setup Progress Bar
        'pbStatus.Value = 0
        'pbStatus.Maximum = 100

        'Determine if ecryption or decryption and setup CryptoStream.
        Select Case Direction
            Case CryptoAction.ActionEncrypt
                csCryptoStream = New CryptoStream(fsOutput, cspRijndael.CreateEncryptor(bytKey, bytIV), CryptoStreamMode.Write)
            Case CryptoAction.ActionDecrypt
                csCryptoStream = New CryptoStream(fsOutput, cspRijndael.CreateDecryptor(bytKey, bytIV), CryptoStreamMode.Write)
        End Select

        'Use While to loop until all of the file is processed.
        While lngBytesProcessed < lngFileLength
            'Read file with the input filestream.
            intBytesInCurrentBlock = fsInput.Read(bytBuffer, 0, 4096)
            'Write output file with the cryptostream.
            csCryptoStream.Write(bytBuffer, 0, intBytesInCurrentBlock)
            'Update lngBytesProcessed
            lngBytesProcessed = lngBytesProcessed + CLng(intBytesInCurrentBlock)
            'Update Progress Bar
            'pbStatus.Value = CInt((lngBytesProcessed / lngFileLength) * 100)
        End While

        'Close FileStreams and CryptoStream.
        csCryptoStream.Close()
        fsInput.Close()
        fsOutput.Close()

        'Catch file not found error.
    Catch When Err.Number = 53 'if file not found
        MsgBox("Please check to make sure the path and filename" + _
                "are correct and if the file exists.", _
                 MsgBoxStyle.Exclamation, "Invalid Path or Filename")

        'Catch all other errors. And delete partial files.
    Catch
        fsInput.Close()
        fsOutput.Close()


    End Try

我应该做些什么来获取byte（）或image从我的文件系统中的加密数据直接到我的应用程序变量。

Answer 1

CryptoStream只是位于另一个Stream之上。当您Write到CryptoStream时，它会传入您传入的Byte数组，对其进行加密并使用结果填充另一个数组，然后它将Write传递给基础Stream。同样，当您致电Read时，它会在基础Read上调用Stream，对其进行解密，然后将结果传递给您。在您的情况下，您使用的是FileStream，但它可以是任何类型的Stream，例如NetworkStream或GZipStream。如果您想要一个临时的地方在您的应用程序中存储二进制数据，那么您可以使用MemoryStream。无论其类型如何，使用Stream的代码都是相同的。

从Crypto Service Provider获取字节或图像

1 个答案: