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.
I have File Like "Sample.bak" and when I compress it to be "Sample.zip" I lose the file extension inside the zip file I meann when I open the compressed file I find "Sample" without any extension.
I use this code :
Dim name As String = Path.GetFileName(filePath).Replace(".Bak", "") Dim source() As Byte = System.IO.File.ReadAllBytes(filePath) Dim compressed() As Byte = ConvertToByteArray(source) System.IO.File.WriteAllBytes(destination & name & ".Bak" & ".zip", compressed)
Or using this code :
Public Sub cmdCompressFile(ByVal FileName As String)
'Stream object that reads file contents Dim streamObj As Stream = New StreamReader(FileName).BaseStream
[CODE]...
I need to compress the file without loosing file extension inside compressed file.
I like to compress the xmldata before the data is provided to the client as an excel file. I am trying to compress and deliver it as a .zip file. its not working Here's my code below. I tried compressing it, converting it to bytes etc etc. The issue with below code is, the XSL transformation is not happening properly and the output excel file is raw xml with some .net exception at the end. (that's what I see on the .xls file that's downloaded at the end) Before I started working on compression my below code was working fine that gives properly formatted excel file from the xml input. the excel file is so nice you can't even tell it was from XML.
I have a program I made in vb.net express 2008 that used java.utils.zip to compress my work files to a Zip archive that I ran occassionaly to have a backup. I worked fine, but with net framework 4 and vb.net 2010 it doesn't work. So I modified it to use sharpziplib and it works fine if all files on the filter list in the folder are closed, but if I have a file open in OpenOffice writer, my program can't access it and won't create the zip file. The file that usually stays open all the time is my TODO list, that is updated several times a day , so usually gets printed, and updated( adding or deleting entries), without closing it.
I'd like to use WinRAR's dll file to compress files in vb.net.Is there any way this can be done? The only one I found was using the unrar.dll to uncompress files. Also, I'd like to know how to implement WinZIP's dlls to compress files as the zipfldr.dll does not achieve very high levels of compression and encryption.
friend of mine has no HTML knowledge so I'm attempting to write a program that replaces certain parts of a html file to suit his needs.I've edited the HTML file and marked certain parts with "tags" like this:
#IMAGEURL1# I have a textbox where he can copy + paste an image URL and hopefully the #IMAGEURL1# is replaced with the contents of the textbox.
So can someone please enlighten me to-as how to open a HTML file (there's no textbox to display the contents just yet, I'll add one if needed), find the specified text and then replace it with whats in a textbox.
How to divide a wav file into two parts. I don't very know how to implement this functionality. If possibly, can you give me detailed code snippet or other some useful link.
I want select portions of the file and then display them on my site,I thought maybe a combination of objReader and a do loop of some description with a delimiter in the text file to indicated when the program should start or stop reading the file.
Is it possible to split a file into like 10 parts, and using multithreading copy it faster and then put it all back together? Will the speed increase or will it stay the same?
I have been investigating xml and find it quite fascinating. Not sure it is worth the effort as far as the sppeed of loading scriptures into a richtextbox.Scenario: User double-clicks in TreeViewLibrary and opens the nodes. He double-clicks on Genesis Chapter 1. Genesis Chapter 1 Verse 1 loads into the RichTextBox.[code]
I 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.
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
Has 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).
I 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]
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.
I 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)
I 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 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 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.
