I keep trying to encrypt a large file using this method: How to encrypt and decrypt a file by using Visual Basic .NET or Visual Basic 2005
However, these files can be upwards of 400MB. Naturally, I keep getting a system.outofmemory ex. Apparently, I can fix this by processing the file in chunks, but I haven't the slightest idea of how to do this.
I have a list of files and all of them have a different size. I need to upload them in chunks of 250Kb (or less if it's a small file or if it's the last chunk of a file).What I would like to do is read a bunch of chunks (lets say 15 chunks), in a separate thread, and then store the chunks of data in some sort of list. This list must be available to other threads.
An upload thread (I don't need help with uploading itself) takes the first chunk from the list and marks the chunk as "currently being uploaded". When the chunk has been fully uploaded, then the chunk is removed from the list. A second upload thread takes the next available chunk in the list that has not been set to "currently being uploaded", etc. There are a total of 10 upload threads working at the same time.
As soon as a chunk is removed from the list, then a new chunk of data is read and added to the list.Does anybody know what kind of list I need or how I should do something like this? I don't expect people to write out the code for me, but I have no idea where to start with this.
So I have a connection string which is read from a basic text file. This string contains a password. Is there anyway to encrypt this text file so that anyone can't just open it up and read it. The program will still be able to read it.
View 5 RepliesI have been successful in making an anti-hack program that uses a list from the local computer, this is at the moment a text file that can easily be modified, so my question is.Is there a way to replace this .txt file with a more secure format, one that cannot be decrypted (or is very hard to decrypt) without changing all my code?
the only thing i have to use the txt file for is adding the contained items to a listbox. Also, it would be possible for be to use SQL as i am using a dedicated server for the automatic update, so can use it as a remote library for the app the connect to.
I am coding a file downloader, when I got over this problem. I can not figure out how to download files in chucks.-file-chunks.htmlbut since it's not answered yet, I'm reposting it here kind of.
View 13 RepliesI have a large wikipedia dump that I want to cut into different files (1 file for each article). I wrote a VB App to do it for me, but it was quite slow and crapped out after a few hours of cutting. Im currently splitting the file into smaller 50mb chunks using another app but thats taking a long time (20-30 minutes for each chunk). I should be able to cut each of these up individually if I do this.
Does anyone have any suggestions of a way to cut this file up quicker?
I've been trying to create my own backup system by sending specific files to a server running on my desktop, and then having those files copied to an external. So far, I'm trying to send files using a tcp network. Unfortunately, for soem reason, tcp cannot send more than 9kb at a time, so when i tried to send a 30kb image, it recreated 1/3 of it. My fix to this problem was to send data by chunks of 8kb, then reconstruct the file chunk by chunk. For some reason, when I run the server and client, the client says it sends all the data, however the server seems to be stuck. Here is my code;
[Code]...
I'm having trouble writing the code to encrypt a file->networkstream->Decrypt the file.. I've tried several ways, but I keep failing....
View 1 RepliesI would like to know if it is possible to be able to encrypt a file and have my application be able to decrypt it and ammed the file as necessary. and then when the program exits it will encrypt the file back up.
View 4 RepliesI want to get some HTTP source with VB.net. The page is huge though, so it would suit me to pull it in chunks. I'm also already reading about the VB.net background worker. So far I'm using this code: HTTP GET in VB.NET but my program stalls while it loads the page, for a decent amount of time. The page to get is http://ftp.drupal.org/files/projects/, but don't go there unless you absolutely have to.
Should I stick with the background worker, and/or is there a way to split up the HTTP request?
I'm just getting started with Visual Basic .NET and I'm currently stuck on the following problem: how can I encrypt/decrypt a file with asymmetric encryption?
Essentially, I'm trying to figure out how I can write the following pseudocode in VB
[code]...
I have a class with a lot of methods. This class and methods are in one file. These methods can be put into 3 groups based on the things that they can be used for. What would be a good way to break these methods up into the 3 groups? I was thinking about doing a partial class definition and breaking up these methods into 3 files.
View 3 RepliesHas anyone used these methods? I tried File.Encrypt on a text file, and I did not get an exception, however the Encrypt method did not work (the file was unchanged afterwards).
View 3 RepliesI need some help on saving/reading xml from/to dataset. I would like to make that complete file is encrypted and not only some elements inside or part of file.Currently this is not working in any way at all.[code]
View 14 RepliesIs it possible to encrypt a file/folder in vb.net?
View 3 RepliesI ended up getting this properly working, as far as encrypting a file goes:How to encrypt and decrypt a file by using Visual Basic .NET or Visual Basic 2005 However, the catch is I have to change the name of the output file. What I was hoping to do is overwrite the original with the encrypted file, but when I tried that on a large file, it ended up only getting about 8 bytes of it.
Does anybody have any suggestions or recommendations? The overall idea is that I want to keep a file encrypted until it needs to be unencrypted for use by a program, but I'm not sure if there are better tools out there or if there's a better way of accomplishing this.
Question 2: I would really, really like to encrypt an entire folder, which I'm guessing would be faster than file by file, but when I try I keep getting access denied errors, even with DOS Cipher. Is there a way to do this with a key?
I made a program that encrypts data and puts it on a txt file. There are two parts of information that need to be "linked" to the other. Say its Person 1, then Person 1 gender, they need to be placed together. Each encrypted piece of seperated by a ";". I have it read the file and place the information on a Rich Text Box. How can I read all the encrypted info and stop at ";" then place that into a variable then read the next bit? I did this a while back but I used StreamReader/StreamWrite and can't remember how I did it. Right now it reads through the open file dialog and writes it to the Text Box with this command writetext.LoadFile(sFilePath, RichTextBoxStreamType.PlainText)
View 4 RepliesHow to encrypt or set a password for my AVI file with visual studio 2008?
View 1 RepliesI have a page that has a few text boxes on it and are filled based upon a persons information. Like Name, telephone number, address etc
The data is stored in an Access DB.
I want to add a check box and have a label beside it that if it's checked it shows a hyperlink to a pdf file, if its not checked the link disappears, so toggle between the two.
Here's the check box I have so far, which isn't much:
<br><input type=checkbox name="Password" value="<%=oRs("Password")%>" size=40> Check to show PDF File: <a href="<%=oRs("Password")%>"><%=oRs("Password")%></a><br><br>
I need this hyperlink/ string to be encrypted based upon the persons name, so each person has its own pdf file and no one can just guess anothers pdf file and have access to it....
The pdf file will be stored in a virtual directory within the site.
I don't know Vb or asp, and I'm doing this all in notepad ++
I need to encrypt vbs file using a cryptographic algorithm. I read about converting it into vbe file, but is there any other way to do it?
View 1 RepliesI have the files in a listview control, with checkboxes. I would like it to encrypt all files ending with .rc4, that are listed in the listview. But keep the original of file extension
E.g : file.txt --> file_txt.rc4
How can I get it to encrypt multiple items. I already tried and still can't write in...
Here my code
Private Sub BtnEncrypt_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnEncrypt.Click
Dim ByteConverter As Encoding = Encoding.UTF8
Dim Key As Byte() = ByteConverter.GetBytes(TextBox2.Text)
If ListView1.Items.Count <> 0 Then
[Code] .....
i am looking to decrypt my HEX code file for an ATTiny chip and programming it using the AVRDude command line interface. Problem being, i do not want the user to be able to see what the HEX file is at any given time.Can the VB.net Cryptography crypt the HEX file before i put it onto the server and then decrypt it after the program downloads it from the server and runs it through the program without seeing the decrypted HEX file?Obviously the HEX file can not stay encrypted while being programmed to the ATTiny chip so how can i go about it so that i can create the original HEX file to be programmed within the program without having to worry about it writing a temporary file to the hard drive and then deleting it afterwards? (Because they could close the program after it does that temp file and they would be able to navigate and open it and see the code)
View 3 Repliesi am looking to decrypt my HEX code file for an ATTiny chip and programming it using the AVRDude command line interface. Problem being, i do not want the user to be able to see what the HEX file is at any given time.
Can the VB.net Cryptography crypt the HEX file before i put it onto the server and then decrypt it after the program downloads it from the server and runs it through the program without seeing the decrypted HEX file?
Obviously the HEX file can not stay encrypted while being programmed to the ATTiny chip so how can i go about it so that i can create the original HEX file to be programmed within the program without having to worry about it writing a temporary file to the hard drive and then deleting it afterwards? (Because they could close the program after it does that temp file and they would be able to navigate and open it and see the code)
i am looking to decrypt my HEX code file for an ATTiny chip and programming it using the AVRDude command line interface. Problem being, i do not want the user to be able to see what the HEX file is at any given time.
Can the VB.net Cryptography crypt the HEX file before i put it onto the server and then decrypt it after the program downloads it from the server and runs it through the program without seeing the decrypted HEX file?
Obviously the HEX file can not stay encrypted while being programmed to the ATTiny chip so how can i go about it so that i can create the original HEX file to be programmed within the program without having to worry about it writing a temporary file to the hard drive and then deleting it afterwards? (Because they could close the program after it does that temp file and they would be able to navigate and open it and see the code)
I tried with the following code. It encrypted the file but after I FTP'd the file to my vendor he was not able to decrypt it.Then realized that this code is not using my PGP Keys to encrypt the file. It's creating a new key automatically. That's the reason my vendor is not able to decrypt the file. How can I encrypt the file using my PGP keys? So that my vendor can decrypt the file using same PGP keys.
' Encrypt textfile with Rijndael encryption
Public
Shared
Sub Encrypt(ByVal[code].....
How can i encrypt or decrypt only a part of a file? I try, and i keep getting an error message that says that the stream might be corrupt. By the way, it is ok to convert the text to a byte array using the system.text.encoding.ascii.getbytes() right? The reason i want to encrypt/compress only a part of a file is because i don't want to encrypt or compress the file header. That way the program can gather info about whether the file is compressed or encrypted.
View 1 Replieswhat is the difference between DPAPI and file.encrypt (I/O)?
View 1 RepliesI've attempted using code snippets as a test to encrypt a string, save it to a file & the reload it back, decrypting it. I consistently get a "Padding is invalid and cannot be removed." error on decrypting the string.
View 3 RepliesI am interested in knowing if non-text files like .xls/.xlsx or .doc files can be encrypted... From the Devlopers Guide on MSDN, I found code snippets that allow encryption / decryption of .txt files. This works absolutely fine. However, I would like to know if similar procedure can be used to encrypt/decrypt file other than .txt file.
View 1 RepliesI have created a encryptor/decryptor that allows you to encrypt/decrypt text in a textbox, or a file. The basis of the system is to allow a user to thoroughly protect data within their system. Is there anyone that would be willing to test the program?
View 4 Replies