Visual Basic

16-Nov-10 13:23

I don't know how many times I've googled this and everything I've looked at doesn't give me a clear answer on what to do. I have file that has combined of many files. An example is |.jpeg|.txt|etc| (file). I know you can't delete from a encrypted file when shouldn't be all that hard to decrypt the file. However, my problem is deleting the .txt in the file.

There it will start out |.jpeg|.txt|etc|

but after running some code it will en up as |.jpeg|etc|

I've used fileStream which I've tried deleting from encrypted and decrypted files. Anything good will help.

Dave Kreskowiak16-Nov-10 14:55

16-Nov-10 14:55

Without more information, it's impossible to help you. You have to know what that file format is (office XML, .ZIP, .RAR, ...) that is holding these files. If it's a custom file format, you're going ot have to find a library or SDK that specifically handles it or write your own. But, in order to do that, you MUST know the exact details of what makes up the archive file format. Without that, you're SOL.

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Dave Kreskowiak

crain198116-Nov-10 16:26

16-Nov-10 16:26

Well... its a custom made format(.fva). All files are encrypted and made into one file. Than when you want to extract from the file, the application will decrypt and extract the file for you. However, the location/position of the data within the file is in an xml but I'm not having any trouble with this part.

However one problem that's been annoying me for about a week is when you encryption small files, its hard to decrypt it(I'll post the code soon).

The second problem is when you delete from the datagridview. Here is the use case:
1. User selects file from datagridview.
2. User presses delete to delete the file.
3. Application deletes the file in the secure archive location.(this is the problem)
4. Application deletes the file from the xml.(not a problem)
5. Application keeps running until user exits out.

Here is the full code below. Please note I've deleted from the problem section because I've been trying things and googling alot lately.

Imports System.Xml
Imports System.Object
Imports System.Security
Imports System.Security.Cryptography

Imports System.IO
Imports System.IO.Compression
Imports Ionic.Zip


Public Class EncryptDecryptForm
    Public index As Integer
    Private Sub EncryptDecryptFormClosing(ByVal sender As Object, ByVal e As System.Windows.Forms.FormClosingEventArgs) Handles Me.FormClosing

        File_DataGridView.Rows.Clear()
        Environment.Exit(0)
    End Sub



    Private Sub Encrypt_Browse_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Encrypt_Browse.Click
        'The code below will open a dialog bos '
        Dim find As OpenFileDialog = New OpenFileDialog()
        find.Title = "File Vault application" 'Title of file browser'
        find.InitialDirectory = "c:\"
        find.AddExtension = True
        find.Filter = "All files (*.*)|*.*|All files (*.*)|*.*"
        find.FilterIndex = 2
        find.RestoreDirectory = True
        If find.ShowDialog() = Windows.Forms.DialogResult.OK Then
            Me.Encrypt_TextBox.Text = find.FileName


        End If
    End Sub

    Private Sub Decrypt_Browse_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Decrypt_Browse.Click
        'Code below will start the folder browser'
        Dim folder As FolderBrowserDialog = New FolderBrowserDialog()
        folder.Description = "Select Folder"
        folder.RootFolder = Environment.SpecialFolder.MyComputer
        If folder.ShowDialog = Windows.Forms.DialogResult.OK Then
            Me.Decrypt_TextBox.Text = folder.SelectedPath.ToString
        End If

    End Sub



    Private Sub Encrypt_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Encrypt.Click
        encryption()
    End Sub
    Private Sub reload()
        'This functions reloads the datagrid with the new updated information'
        'Replaces the format so the application can read it'
        
        Dim xdoc As XmlDocument = New XmlDocument
        xdoc.Load("Resources\FileVault.xml")
        Dim name As XmlNodeList = xdoc.GetElementsByTagName("*******")
        Dim count As Integer
        For count = 0 To (name.Count - 1)
            File_DataGridView.Rows.Add(name.Item(count).InnerText.ToString, name.Item(count).InnerText.ToString)
        Next count
        File_DataGridView.AutoResizeColumns()
        File_DataGridView.AutoResizeRows()

    End Sub


    Private Sub Decrypt_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Decrypt.Click
        decryption()

    End Sub
    


    Private Sub EncryptDecryptForm_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        'When the forms load, this sets up the initial columns and what the user can and can not do to them.'
        File_DataGridView.Columns.Add("File name", "File name")
        File_DataGridView.ColumnHeadersVisible = True
        File_DataGridView.ColumnCount = 1
        File_DataGridView.AllowUserToResizeColumns = False
        File_DataGridView.AllowUserToAddRows = False
        File_DataGridView.AllowUserToResizeRows = False
        File_DataGridView.AllowUserToOrderColumns = False
        File_DataGridView.AllowDrop = False
        File_DataGridView.AllowUserToDeleteRows = True
        File_DataGridView.AutoGenerateColumns = True



        Dim xdoc As XmlDocument = New XmlDocument

        xdoc.Load("Resources\FileVault.xml") 'Load Xml file -> declare location here'
        Dim name As XmlNodeList = xdoc.GetElementsByTagName("*******") 'Counts these elements'

        Dim count As Integer
        For count = 0 To (name.Count - 1) 'This for loop fills the data'
            File_DataGridView.Rows.Add(name.Item(count).InnerText.ToString, name.Item(count).InnerText.ToString)
        Next count


        

    End Sub

    'This function creates the encryption key' 
    Private Function keyencryption(ByVal strPassword As String) As Byte()
        'Converting the character to an array and storing the data
        Dim chrdata() As Char = strPassword.ToCharArray

        'Make is the same length'
        Dim Length As Integer = chrdata.GetUpperBound(0)

        'starting to hash the data'
        Dim bytDataToHash(Length) As Byte

        For i As Integer = 0 To chrdata.GetUpperBound(0)
            bytDataToHash(i) = CByte(Asc(chrdata(i)))
        Next

        'Declaring what Hash to use'
        Dim SHA512 As New System.Security.Cryptography.SHA512Managed

        'Hashing'
        Dim Result As Byte() = SHA512.ComputeHash(bytDataToHash)

        Dim resIV(31) As Byte

        For i As Integer = 0 To 31
            resIV(i) = Result(i)
        Next
        Return resIV
    End Function

    'Identical function from above except for a few lines
    Private Function IVCreation(ByVal strPassword As String) As Byte()
        'Converting the character to an array and storing the data
        Dim chrdata() As Char = strPassword.ToCharArray

        'Make is the same length'
        Dim Length As Integer = chrdata.GetUpperBound(0)

        'starting to hash the data'
        Dim bytDataToHash(Length) As Byte

        For i As Integer = 0 To chrdata.GetUpperBound(0)
            bytDataToHash(i) = CByte(Asc(chrdata(i)))
        Next

        'Declaring what Hash to use'
        Dim SHA512 As New System.Security.Cryptography.SHA512Managed

        'Hashing'
        Dim Result As Byte() = SHA512.ComputeHash(bytDataToHash)

        Dim resIV(15) As Byte

        For i As Integer = 32 To 47
            resIV(i - 32) = Result(i)
        Next
        Return resIV
    End Function

    Private Function encryption()

        'This sub will encrypt the file, xml edits, update the gridview'
        'loading the xml document'
        Dim xdoc As XmlDocument = New XmlDocument
        Dim key As Byte()
        Dim IV As Byte()

        'The hardcoded password goes here'
        'This is a section just in case you want to a password to your encrypted files'
        'Right now it uses the hardcoded password'
        'If you can expand this if you want'
        key = keyencryption(LoginForm.Password_TextBox.Text)
        IV = IVCreation(LoginForm.Password_TextBox.Text)
        'if there is an error in the application. A error message will be displayed'
        Try
            'checking to make sure the text box isn't null'
            If (Encrypt_TextBox.Text = "") Then
                MessageBox.Show("Need to put in a file location")
            Else

                


                'Grabing the file name'
                Dim locatefilename As String = Me.Encrypt_TextBox.Text
                Dim i As Integer = 0
                Dim fnPosition As Integer = 0
                'locating all the \ in the string'
                While locatefilename.IndexOf("\"c, i) <> -1
                    fnPosition = locatefilename.IndexOf("\"c, i)
                    i = fnPosition + 1
                End While

                Dim junk As String
                Dim tfile As String
                Dim file As String
                Dim ext As String
                'This should get all the junk that not need for saving files'
                'This should capture what you don't need'
                junk = locatefilename.Substring(0, fnPosition)
                'This should capture the file' 
                tfile = locatefilename.Substring(fnPosition + 1)
                'Zeroing both i and fnPosition'
                i = 0
                fnPosition = 0
                'taking out the extention in the file and saving it to the xml'
                While tfile.IndexOf("."c, i) <> -1
                    fnPosition = tfile.IndexOf("."c, i)
                    i = fnPosition + 1
                End While
                'This should get the actually file name'
                file = tfile.Substring(0, fnPosition)

                'captures the ext (like the txt)'
                'Makes the format of the file invisible but only in the xml'
                ext = "." & tfile.Substring(fnPosition + 1)

                'Checking to make sure there are not duplicate file name'
                Dim name As XmlNodeList = xdoc.GetElementsByTagName("*******")
                Dim cname As Integer
                For cname = 0 To (name.Count - 1)
                    If (file = name.Item(cname).InnerText) Then
                        MessageBox.Show("Duplicate file name - either delete the file present in safe or rename file")
                        Return 1
                    End If
                Next
                'This is the file being read in'
                Dim fileinput As New System.IO.FileStream(Me.Encrypt_TextBox.Text, IO.FileMode.Open, IO.FileAccess.Read)
                'specific file output location here
                Dim fileoutput As New System.IO.FileStream("*******", IO.FileMode.Open, IO.FileAccess.Write)

                Dim start As Integer = fileoutput.Length

                'Declaring variables for encryption'

                Dim buffer(4096) As Byte 'Holds the bytes for processing

                Dim BytesProcessed As Long = 0 'running count for bytes that are processed'

                Dim filelength As Long = fileinput.Length 'Length of file coming in'

                Dim bytesinblock As Integer 'current bytes in block'

                Dim crypto As CryptoStream

                'Declaring crypto service provider'
                Dim scRijndael As New System.Security.Cryptography.RijndaelManaged

                'setting up progress bars
                Encrypt_ProgressBar.Value = 0
                Encrypt_ProgressBar.Maximum = 100

                crypto = New CryptoStream(fileoutput, scRijndael.CreateEncryptor(key, IV), CryptoStreamMode.Write)

                While BytesProcessed < filelength
                    'reading the file'
                    bytesinblock = fileinput.Read(buffer, 0, 4096)
                    'writing the file to cryptoStream'
                    crypto.Write(buffer, 0, bytesinblock)
                    'updating bytes processed'
                    BytesProcessed = BytesProcessed + CLng(bytesinblock)
                    'equation for updating bytes in block'
                    Encrypt_ProgressBar.Value = CInt((BytesProcessed / filelength) * 100)
                End While
                Dim filend As Integer = fileoutput.Length
                crypto.Close()
                fileinput.Close()

                fileoutput.Close()
                MessageBox.Show("File is done encrypting")
                Encrypt_ProgressBar.Step = 0
                Encrypt_ProgressBar.Value = 0
                Encrypt_TextBox.Text = ""
                'End While


           

                'loading the xml file
                xdoc.Load("*******")
                'variable for adding a new line' 
                Dim nline As String = Environment.NewLine
                'Creating string for xml file with proper formats'
                Dim xmlString As String = nline & "   <file>" & nline & "       <name>" & file & "</name>" & nline & "       <location>" & "Safe\" & file & "</location>" & nline & "       <ext>" & ext & "</ext>" & nline & " <beginbyte>" & start & "</beginbyte>" & nline & "    <endbytes>" & filend & "</endbytes>" & nline & "    </file>" & nline
                'the following is used to add the element to the xml'
                Dim frag As XmlDocumentFragment = xdoc.CreateDocumentFragment
                'Adds the xmlstring to the frag'
                frag.InnerXml = xmlString
                Dim xroot As XmlNode = xdoc.DocumentElement
                'the following statements will add on to the file and save the file'
                xroot.AppendChild(frag)
                xdoc.Save("*******")
                'Clearing the datagrid and reloading the new data, to the eye it you will just blink'
                File_DataGridView.Hide()
                File_DataGridView.Rows.Clear()

                'function reloads the updated xml file'
                reload()

                File_DataGridView.Show()


            End If
        Catch ex As Exception
            MsgBox(ex.Message)

        End Try
        Return 1
    End Function
    Private Function decryption()

        'This is function is the same as encryption with just a few changes'
        'loading the xml document'
        Dim xdoc As XmlDocument = New XmlDocument
        Dim key As Byte()
        Dim IV As Byte()

        'The hardcoded password goes here'
        'This is a section just in case you want to a password to your encrypted files'
        key = keyencryption(LoginForm.Password_TextBox.Text)
        IV = IVCreation(LoginForm.Password_TextBox.Text)
        'if there is an error in the application. A error message will be displayed'
        Try

            'checking to make sure the text box isn't null'
            If (Decrypt_TextBox.Text = "") Then
                MessageBox.Show("Need to put in the file location or select file in grid for decryption")
            Else

                'declaring string for file'
                Dim file As String
                Dim tfile As String
                Dim deleteExt As String
                Dim output As String
                Dim fnPosition As Integer
                Dim i As Integer

                'locating the selected file in the gridview'
                'loading the xml file
                xdoc.Load("*******")
                'Declare name for xml node'
                Dim name As XmlNodeList = xdoc.GetElementsByTagName("*******")
                'file location is now saved
                file = name.Item(index).InnerText
                'Substring of file. This is will be convering the file back to its normal
                tfile = file.Substring(5)
                'retrieving the extenstion'
                Dim extname As XmlNodeList = xdoc.GetElementsByTagName("*******")
                Dim replace As String
                deleteExt = extname.Item(index).InnerText
                'replacing with proper format'
                While tfile.IndexOf("."c, i) <> -1
                    fnPosition = tfile.IndexOf("."c, i)
                    i = fnPosition + 1
                End While
                'This should get the actually file name'
                replace = (tfile & deleteExt)
                'setting the output file with proper format'
                output = Decrypt_TextBox.Text & "\" & replace
                Dim filebegin As XmlNodeList = xdoc.GetElementsByTagName("*******")
                Dim filend As XmlNodeList = xdoc.GetElementsByTagName("*******")
                Dim intStart As Integer = filebegin.Item(index).InnerText
                Dim intEnd As Integer = filend.Item(index).InnerText
                'This is go into the Safe and retrieve file'
                Dim fileinput As New System.IO.FileStream("Safe.fva", IO.FileMode.Open, IO.FileAccess.Read)
                'specific file output location wiht proper extension'
                Dim fileoutput As New System.IO.FileStream(output, IO.FileMode.OpenOrCreate, IO.FileAccess.Write)
                'The next line makes sure that the file is empty'
                fileoutput.SetLength(0)

                'Declaring variables for encryption'

                Dim buffer(4096) As Byte 'Holds the bytes for processing

                Dim BytesProcessed As Long = 0 'running count for bytes that are processed'

                Dim filelength As Long = intEnd - intStart 'Length of file coming in where intEnd will be greater than intStart'

                Dim bytesinblock As Integer 'current bytes in block

                Dim crypto As CryptoStream

                'Declaring crypto service provider'
                Dim scRijndael As New System.Security.Cryptography.RijndaelManaged

                'setting up progress bars
                Encrypt_ProgressBar.Value = 0
                Encrypt_ProgressBar.Maximum = 100

                crypto = New CryptoStream(fileoutput, scRijndael.CreateDecryptor(key, IV), CryptoStreamMode.Write)
                fileinput.Position = intStart
                While BytesProcessed < filelength
                    'reading the file'h
                    bytesinblock = fileinput.Read(buffer, 0, 4096)
                    'writing the file to cryptoStream'
                    crypto.Write(buffer, 0, bytesinblock)
                    'updating bytes processed'
                    BytesProcessed = BytesProcessed + CLng(bytesinblock)
                    'equation for updating bytes in block'
                    Decrypt_ProgressBar.Value = CInt((BytesProcessed / filelength) * 100)
                End While
                If (filelength = 0) Then
                    bytesinblock = fileinput.Read(buffer, 0, 4096)
                    crypto.Write(buffer, 0, bytesinblock)
                End If
                crypto.Close()
                fileinput.Close()
                fileoutput.Close()
                MessageBox.Show("File is done decrypting")
                Decrypt_ProgressBar.Step = 0
                Decrypt_ProgressBar.Value = 0
                Decrypt_TextBox.Text = ""
            End If
        Catch ex As Exception
            MsgBox(ex.StackTrace.ToString)
        End Try

        Return 1
    End Function

    Public Sub File_DataGridView_CellContentClick(ByVal sender As System.Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles File_DataGridView.CellClick
        index = e.RowIndex

    End Sub



    Private Sub File_DataGridView_UserDeletingRow(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewRowCancelEventArgs) Handles File_DataGridView.UserDeletingRow
        Dim xdoc As XmlDocument = New XmlDocument
        xdoc.Load("*******")

        Dim filebegin As XmlNodeList = xdoc.GetElementsByTagName("*******")
        Dim filend As XmlNodeList = xdoc.GetElementsByTagName("*******")
        Dim intStart As Integer = filebegin.Item(index).InnerText
        Dim intEnd As Integer = filend.Item(index).InnerText

        Dim deletefile As New System.IO.FileStream("*******", FileMode.Open)
        Dim deletethis As Integer = CLng(deletefile.Length)

        







        'Deletes the actual file'
        Dim location As XmlNodeList = xdoc.GetElementsByTagName("*******")
        Dim del_location As String = location.Item(index).InnerText

        'Deletes the information in the xml'
        Dim name As XmlNodeList = xdoc.GetElementsByTagName("*******")
        name.Item(index).RemoveAll()
        name.Item(index).ParentNode.RemoveChild(name.Item(index))
        xdoc.Save("********")


    End Sub



End Class

All help will be greatly appriecated.

Dave Kreskowiak16-Nov-10 17:15

16-Nov-10 17:15

This has got so many problems I don't know where to start.

First, you've got an XML file that holds all the position data in the archive, but you've got nothing persisting this XML data anywhere. Once you're app is closed, it's gone and you have no hope of decrypting the data in the archive, let alone finding it.

You've got no code at all that removes a file from the archive, nor anything that updates pointers to where the remaining files would now be in the modified archive. You've got nothing to add files, nothing to manage the collection of files and the data, no real data structures tracking this stuff, ... basically, this was done entirely wrong. From what I can see in this code, you've got no hope of fixing this because it has to be completely torn down and a new library created that just handles these custom archive files. Forget the form stuff and getting values from TextBox's. The library shouldn't care at all about TextBox's. It should only get it's data from parameters passed into well crafted methods, such as (an overly simplified list!) AddFile(filepath), DeleteFile(filepath), CreateNewArchive(archivePath), ...

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Dave Kreskowiak

crain198118-Nov-10 13:01

18-Nov-10 13:01

I don't think I need persists when the application isn't going to be web based. I mean it decrypts fine but my problem is deleting the file from the secure file. I understand about the data Structure but this is a application is form based and I have to do it this way. If it was for me, I prolly would use vb to do this.

Dave Kreskowiak18-Nov-10 13:26

18-Nov-10 13:26

No one said anything about this being web-based.

What you have simply isn't going to work - period, end of story. You have nothing managing the format of the file at all, maintaining the indexes where the start of every file is in the archive, which is a non-optional requirement for functionality like this.

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Dave Kreskowiak

crain198118-Nov-10 14:35

18-Nov-10 14:35

What will be used to manage the xml? An object? make it object orientated.

Dave Kreskowiak18-Nov-10 16:58

18-Nov-10 16:58

That's where your data structures come in. You can create your own class that tracks this information and is serializable.

In my humble opinion, Version 1 of my file format would lay out like this:

preamble bytes (signature)
64-bit integer offset of file table
encrypted file1 bytes
encrypted file2 bytes
encrypted file3 bytes
encrypted file4 bytes
encrypted file5 bytes
.
.
.
file table data

By putting the file table data at the end of the file, you make it easier to add and remove files from the archive as every time you close the archive, you have to write the file table to the end of the file, at a easily obtainable offset. Once that is written, you can update the fixed length 64-bit integer offset with the beginning of the file table.

Like I said, this would be my version 1 layout. Version 2 would probably add a file header to each file with checksum and length data and maybe a second copy of the file table data for backup purposes. You could even write a tool to recover salvagable files from a corrupted archive if you so choose.

Why WOULDN'T I do this? Because if the archive gets damaged, your archive isn't supported by ANY recovery and analysis tools used on other well-known file formats, unless you write these tools yourself.

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Dave Kreskowiak

crain198119-Nov-10 1:55

19-Nov-10 1:55

So the file data table will be part of the file and not a external source like the xml? So when I need something out the file, I can pull this and check it and than extract the information.

Dave Kreskowiak19-Nov-10 10:29

19-Nov-10 10:29

Yep. Everything in one file and you can easily Seek to anywhere in the file any read/write any number of bytes, so long as you know the file format.

The only problem with a solution like this is when doing file operations in the archive, the easiest implementation maintains the entire file table in memory for the life of the set of operations and gets written out only when the archive is closed. If the machine loses power during this time, you've just corrupted the archive file.

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Dave Kreskowiak

crain198119-Nov-10 11:44

19-Nov-10 11:44

Private Sub CreateDataTable()
       'Creates a better way for securing data'
       Dim parent As DataTable = New DataTable("ParentTable")
       Dim column As DataColumn = New DataColumn
       column.DataType = System.Type.GetType("System.String")
       column.ColumnName = "FileName"
       column.Unique = True
       column.ReadOnly = False
       parent.Columns.Add(column)

       'Creating a second column'
       column = New DataColumn()
       column.DataType = System.Type.GetType("System.Byte")
       column.ColumnName = "Size of File"
       column.Unique = False
       column.ReadOnly = True
       parent.Columns.Add(column)

       'Creating columns for storing data positions'
       column = New DataColumn
       column.DataType = System.Type.GetType("System.String")
       column.ColumnName = "File starting Location"
       column.Unique = True
       column.ReadOnly = True
       parent.Columns.Add(column)
   End Sub

Dave Kreskowiak20-Nov-10 13:59

20-Nov-10 13:59

You shouldn't be using a DataTable for this. It's too heavy an object to serialize into your achive file. Create a structure that hold this information, then create a generic collection to hold instances of this structure. For example:

<Serializable> _
Public Structure FileRecord
    Public FileName As String
    Public PositionOffset As Long
    Public EncryptedLength As Long
    Public OriginalLength As Long
End Structure

These would be held in a collection declared like this:

Dim fileRecords As New List(Of FileRecord)
.
.
.
Dim newFile As FileRecord
newFile.FileName = "blahh.bla"
newFile.PositionOffset = whateverOffset
newFile.EncryptedLength = whateverByteLength
newFile.OriginalLength = whateverOriginalFileWas
fileRecords.Add( newFile )

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Dave Kreskowiak

crain198120-Nov-10 14:52

20-Nov-10 14:52

Ok I'll do that.

Which do you think is better? FileStream or BinaryWriter & BinaryReader? When I'm using FileStream the file doesn't go past 194,000KB and it doesn't get any larger.

crain198119-Nov-10 11:11

19-Nov-10 11:11

Dave,

Its been a while since I've programmed in vb but I'm going to implement a data table and post it on here to see if I'm going in the correct direction.

Dave Kreskowiak18-Nov-10 13:30

18-Nov-10 13:30

If you're talking about keeping users from deleting the archive file, the only way to do that would be to protect the file and it's parent folder with appropriate NTFS permissions.

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Dave Kreskowiak

Luc Pattyn16-Nov-10 17:24

Luc Pattyn

16-Nov-10 17:24

I concur with Dave.
I would like to add I don't like encryption or packaging schemes that result in two files; IMO the net result should be a single file, avoiding all possible catastrophes when one file is lost, or the two files don't match together.

What reasons do you have not to use a popular format (ZIP, TAR, ...) and the existing tools or libraries?

Smile | :)

Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles] Nil Volentibus Arduum

Please use <PRE> tags for code snippets, they preserve indentation, and improve readability.

crain198118-Nov-10 12:24

18-Nov-10 12:24

When I asked what was going on, I was about to pull my hair out but after taking a break and coming back I see everything you two are saying. However, this application depends heavily on two forms, its not a web based application, it can't have a database, using .net framework 2.0 so I'm was very Mad | :mad:

. First Sorry Dave and company for going off. But I really do need some help and would like to build this program as professionally as possible. However, I can't get rid of the forms. Would you people help me out? I see what you mean by pointers but I can't use zip. I distributed it to my customer before and he rejected it because I had to delete the file and he wants it so the OS can't read it. I have the algorithm to do the work but after finding out that he wants 5GB files and very small files. This application will not work for that. I'm going to start this application all over and the file safe.fva is where the file will encrypted and stored. Central location... any help at this time with this will be good.

Dave Kreskowiak18-Nov-10 13:28

18-Nov-10 13:28

OK, this requires that you maintain a filesystem inside a file, which REQUIRES maintaining all this data so that you can perform these file operations and rewrite the archive file as appropriate. You simply have no choice here. What you have isn't going to do the job for you at all. It needs a much more complex solution, which we've already explained.

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Dave Kreskowiak

crain198118-Nov-10 14:34

18-Nov-10 14:34

Ok... I do need to encrypt this is required. I hate that its required but it needs to be done.

crain198119-Nov-10 15:05

19-Nov-10 15:05

Why does the doesn't go any further than 194,000 kb?

Dave Kreskowiak20-Nov-10 13:18

DatagridView combined with DataSet

20-Nov-10 13:18

I have no idea what you're talking about...

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Dave Kreskowiak

jan_le15-Nov-10 21:48

jan_le

15-Nov-10 21:48

Hi, I tried do use an typed DataSet (with 2 Tables, 1 Master-detail-Relation),
and wrote:

DataGridView1.DataSource = DataSet1

the Gridview shows the columns well, but null data, null rows.

A Method like DataSet1.Fill I missing, you can me help, how the Data load in the DataSet?

Many thanks, Jan.

Re: DatagridView combined with DataSet

Scubapro15-Nov-10 22:30

Scubapro

15-Nov-10 22:30

Since your DataSet1 contains 2 Tables, you'll have to set the table you'll want to show.
So use:

DataGridView1.DataSource = DataSet1.Tables("TableName")

Re: DatagridView combined with DataSet

jan_le16-Nov-10 3:20

jan_le

16-Nov-10 3:20

it dosn´t work. may be, the relation between master and detail not is correct?

Im using mysqlconnector 5.1 and made the dataset in vs2008-datenquellen.
the datas are in the dataset - with xml i can all export.
but in the grid nothing to see.....

please help ......

Re: DatagridView combined with DataSet

Dave Kreskowiak16-Nov-10 3:46