Fail To Make A Text Encryption And Decryption Program
Nov 13, 2011I am trying and failing to make a text encryption and decryption program. How can I encrypt and decrypt text or text files?
View 6 Replies
ADVERTISEMENT
Encryption Of A Text File + Decryption For Security Program?
Feb 10, 2011What I've decided to start working on is pretty much a personal project but something I may use in my UNI course in due time. I'm creating a security program with a set of access codes (yes I am a bit of a star trek fan) - 4 in total to be exact. I want to be able to use an Encrypted key file in form of a simple notepad created text file to update the codes at any due time. All I'm looking to do is write the access codes to the text file (say for a friend to use the program), Encrypt the file through the program and be able to also decrypt to obtain the new access codes on demand also via the same program. Once decrypted the codes can be read and verified if the user has entered each one correctly. I could hard code the access codes into the program but would rather do it the way I've thought of.
Back in the days of the old VB6 there was a simple method but for some reason that doesnt work any more. What I guess I'm looking to do is have 4 text fields where 4 digit access codes are typed into, have the program take them and encrypt each one is then written to the text file. Hoping that will make it a bit clearer what I'm trying to achieve as I think I made it sound like I want to encrypt the text file after the info has been written to it, which is of course one option so wouldn't mind know how to do that too!
Make A Key That Will Be Used In File Encryption/decryption For An Application?
Jul 12, 2011I am trying to make a key that will be used in file encryption/decryption for my application. However, there is no user data involved with this application (As i would usually use the user's password to generate the encryption key), so i have to turn to another method.
I am thinking that maybe it is possible to generate a completely random key the first time the program runs, then save this key inside the program so that it is inaccessible by the user. The user will not be shown this key, but the key MUST be randomly generated for each application, and it also must stay constant once it is created.
Encryption Decryption To And From Text-box
May 17, 2009At the moment I have a Form containing two text boxes and two buttons. I want the one textbox to be used to type a message (to be encrypted) and the second textbox will be for a key to decrypt the message. Button one will be for encryption and button 2 for decryption.
View 7 RepliesEncryption / Decryption Program - Slow Process
Jul 18, 2010I was board making web browsers and OS so, I tried making an Encryption/Decryption program. I surfed the net and found a source code. But, after doing everything, I debug it, click the encrypt btn and nothing happens. I though the encrypting is a slow process. The thing is the process should be immediate cause I downloaded this web browser called 'Areo Pack'. It comes with a few other program and one of them in an Encryption/Decryption program. I tried it and it was done in a few seconds. I tried opening the encrypted file with notepad and I see a text file with Chinese, Japaneses, Korean, etc.
Imports System.Security.Cryptography
Imports System.Text
Public Class Form1
Private Shared DES As New TripleDESCryptoServiceProvider
Private Shared MD5 As New MD5CryptoServiceProvider
[Code] .....
Simple Encryption / Decryption Program Does Not Process
Aug 13, 2009This is for a simple encryption / decryption program. However when I run this the program does nothing and doesnt respond. Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim decryptedtext As String
Dim encryptedtext As String
Dim k As Int16
[code]...
AES Encryption / Decryption
Feb 1, 2012Here is some code that works well for strings:
[Code]....
modifying these functions to encrypt/decrypt byte arrays rather than strings. Also, to have the functions return the encrypted/decrypted byte array, rather than a string.
Database Encryption And Decryption?
Jun 29, 2011encrypt MS Access database and also decrypt it.
My purpose is to encrypt the database so that it cannot be open independently without using the application. my application should still be able to access it read/write.
Encryption/Decryption Using Webservice?
Jun 24, 2009From desktop application I want to upload an image. Then want to pass that image to webservice which encrypt it and pass it to another webservice which will save the encrypted image in the Access database. And then using ASP.net want to decrypt the image.
View 2 RepliesEncryption/Decryption With RijndaelManaged?
May 28, 2009I have a Problem to Decrypt my crypted files :e.g. if I encrypt this text:
B�AR B�LASDJASPDJAPSDJPASDJPASD
asdj
...
And Decrypt it:
AB0_�-M3‚S�r�WPJAPSDJPASDJPASD
asdj
...
The first chars are wrong! My Code to Encrypt and Decrypt :
Encrypt:
Public Shared Sub EncryptFile(ByVal sSource As String, ByVal sTarget As String, Optional ByVal BufferSize As Long = 4096)
Dim ErrorHappened As Boolean = False
Dim OldFileStream As FileStream
Dim NewFileStream As FileStream
[code].....
Javascript Encryption And .net Decryption?
Oct 11, 2011I need to encrypt a string using javascript and decrypt it using vb.net, is there a compatible encryption/decryption method between javascript and vb.net to be used?
View 5 RepliesVIDEO ENCRYPTION DECRYPTION
Jul 16, 2009[Code] I need to do a video encryption/decryption on p2p chat. The concept for my understanding is to capture the video, encode it then encrypt, on the receiver side is to decode and decrypt it.
View 1 RepliesError On Encryption/decryption Files
Jan 31, 2010When I decrypt an encrypted file; it doesn't have the same size in bytes as the original file and the the hash of the file is different.
I get the bytes of the file using File.ReadAllBytes and send to EncryptBytes with the password. Also the same with DecryptBytes.
When I receive the bytes encrypted or decrypted i save them using File.WriteAllBytes.
I need that the decrypted file and original file have the same hash an bytes.
This my code:
Public Function EncryptBytes(ByVal pass As String, ByVal bytes() As Byte)
Dim myRijndael As New RijndaelManaged
myRijndael.Padding = PaddingMode.Zeros
myRijndael.KeySize = 256
[Code].....
Implement Encryption And Decryption Algorithms?
Nov 30, 2010How to implement encryption and decryption algorithms in vb.net? Which algorithm is the best suited one?
View 4 RepliesXML Encryption/Decryption In Separate Files?
Apr 27, 2011I need to encrypt an XML file, send it to another location and decrypt it there. As you can see from the codes below, I am using the same key but it won't work (for now im simply using two local files).
The error I get is as follows:
Padding is invalid and cannot be removed.on this line in Decrypt.aspx: Dim xReader As XmlTextReader I am thinking it might be at the actual encryption stage causing errors e.g., file not saving correctly.
Encrypt.aspx
Dim rijnAlg As RijndaelManaged
rijnAlg = RijndaelManaged.Create()
[code]......
Easy Encryption / Decryption Method For Strings
Jul 26, 2011I'm trying to find a simple and easy encryption/decryption method for strings. The strings will contain spaces, special characters, numbers, and letters. I just need to be able to encrypt/decrypt them.
View 3 RepliesSecure(ish) Encryption/decryption Algorithms Using A String As A Key?
Aug 25, 2009Is there a way to encrypt/decrypt text (string form) in VB.net using another string as a key? Meaning, if one user encrypts using this key, the other user needs to decrypt using the same key?I do NOT mean public and private key encryption or anything of the sort.If not, what is the second best way to encrypt/decrypt data without public/private keys?I want to make a simple way to send messages securely.
View 2 RepliesVS 2005 Encryption/Decryption With Crytography Classes?
Aug 25, 2009I'm using the cryptography classes in .net to encrypt and decrypt files. When I encrypt a txt file, then decrypt in my code it works fine. But when I encrypt an xml file and try to decrypt it within my code I get an error saying "padding is invalid and cannot be removed." I am setting the padding during both the encryption and decryption as:
PaddingMode.PKCS7. Do you think the file being an xml file has something to do with the error that's occuring? Also, should I or should I not be setting the padding for both encryption and decryption?
Complete VB Project Of Image Encryption And Decryption With Codes?
Mar 17, 2010Complete VB project of Image Encryption And Decryption with codes
View 4 RepliesVS 2010 Filesize Is Same As Original After Encryption / Decryption Process
Jun 22, 2011I have (using some examples) created a program which reads from a file, encrypts the content and writes it to a new file. The file can then be reopened in the program and decrypted.Now I am trying to adapt the program to split the file into pieces as specified by the user whilst it is been written to the hard drive. This also works, but when the files are read and decrypted the original file seems to be corrupted. I have been testing it using a JPG which turns out viewable, but is distorted. However the filesize is the same as the orignal after the encryption/decryption process. [code]
View 3 RepliesMake An Encryption Program?
May 12, 2010My idea is to have an input and an output text box. When the user presses a button the program will encode what is in the input text box and output it into the output text box.I also want to encrypt it with a secret key where the user enters a letter or set of letters into a separate text box which will effect the output. This process can be reversed to decrypt
View 4 RepliesRijnDael Encryption/decryption - Select The Key Bytes And The Block Bytes From The Numeric Up/down?
Nov 13, 2010I want it to do is that you input a string, then you select an algorithm (Theres only going to be one RijnDael) then you input a key, then the Initialization Vector comes from "txtIV.text" then you select the key bytes and the block bytes from the numeric up/down, then you either encrypt or decrypt.
View 1 RepliesEncryption/Decryption - Code To Encrypt A File->networkstream->Decrypt The File
Feb 28, 2011I'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 RepliesWriting A Program That Will Encrypt Text Using AES Encryption
Feb 14, 2009I need some help with writing a program that will encrypt text using AES encryption. I'm not quite sure how to go about doing this.
View 1 Replies.netCART Credit Card Decryption - IIS 7 App Pool And Decryption?
May 18, 2009I've got a site using .netCART. It's running fine in production with Windows Server 2003 and .NET 2.0. On the new server (Windows Server 2008) everything is working except for credit card decryption in the store admin. No errors are being sent, no exceptions thrown, just the encrypted string being output to the screen instead of a decrypted credit card number.
Dim strCCEncrypt As String
strCCEncrypt = Trim(DataRow.Item("CreditCard"))
strCCEncrypt = tools.Decrypt(strCCEncrypt) 'tools is a .netCART utility
[code].....
Make A Program That Sends Text In The Text Box To A Form On A Website And Print The Page As .xps
Aug 30, 2010I want to make a program that sends text in the text box to a form on a website and print the page as .xps
View 2 RepliesVS 2010 Make A Program In Which If The Textbox Text And The Listbox Text Are The Same Order?
Apr 25, 2012im trying to make a program in which if the textbox text and the listbox text are the same order, which they are in the picture, a bluie fonted text saying well done appears. However only the red text appears which is only meant to come when the order of the text in both listbox and textbox isnt the same.
Here is the code that i used for this:
listarrays = name of listbox
textbox1 = name of textbox
l is the name of the label for correct answer(blue font)label3 is name of label with red font which should only appear for wrong answer
Dim text As String = Me.TextBox1.Text
For Each item As Object In listarrays.Items
If item.ToString = Me.TextBox1.Text Then
[code].....
use another textbox instead of the listbox but thats just making itmuch harder for me as I already made the full code working with the listbox. My lecturer told me i need to convert both in string so both textbox and listbox are compatible and i did so (see code above) but the correct label doesn't show?
How To Do An Encryption Program That Encrypts With AES256
May 15, 2010I'm trying to do an encryption program that encrypts with AES256. I have searched for source codes, but I could not find proper result. Most of programs use Rijndael as algorithm, but I don't want using this class. I searched MSDN for AES classes, and I found AESCryptoServiceProvider, but I don't know how to use it.
View 4 RepliesList Encryption Types In Program?
Oct 31, 2011Could any one list the encryption types in Visual Basic.
View 1 RepliesProgram License Generation And Encryption?
Jul 20, 2010Public Function Crypt(ByVal Str As String, ByVal Password As String) As String
Dim SK As Long, K As Long
Rnd(-1)
Randomize(Len(Password))
[code]....