RC2 object to encrypt and decrypt data in a file in VB.Net
In this tutorial we will learn how to use RC2 object to encrypt and decrypt data in a file.
This is the method by which we can encrypt and decrypt the data in the file. It is an important part of Security used in VB.Net application.
1. Open visual studio and create a project
2. Add the following assembly on the page
Imports System.Security.Cryptography
Imports System.Text
Imports System.IO
3. Now write the following code for Encryption and Decryption
Module RC2Sample
Sub Main()
Try
Dim RC2alg As RC2 = RC2.Create("RC2")
Dim sData As String = "My name is yahoo"
Dim FileName As String = "CText.txt"
EncryptTextToFile(sData, FileName, RC2alg.Key, RC2alg.IV)
Dim Final As String = DecryptTextFromFile(FileName, RC2alg.Key, RC2alg.IV)
Console.WriteLine(Final)
Catch e As Exception
Console.WriteLine(e.Message)
End Try
Console.ReadLine()
End Sub
Sub EncryptTextToFile(ByVal Data As String, ByVal FileName As String, ByVal Key() As Byte, ByVal IV() As Byte)
Try
Dim fStream As FileStream = File.Open(FileName, FileMode.OpenOrCreate)
Dim RC2alg As RC2 = RC2.Create
Dim cStream As New CryptoStream(fStream, RC2alg.CreateEncryptor(Key, IV), CryptoStreamMode.Write)
Dim sWriter As New StreamWriter(cStream)
sWriter.WriteLine(Data)
sWriter.Close()
cStream.Close()
fStream.Close()
Catch e As CryptographicException
Console.WriteLine("A Cryptographic error occurred: {0}", e.Message)
Catch e As UnauthorizedAccessException
Console.WriteLine("A file error occurred: {0}", e.Message)
End Try
Console.ReadLine()
End Sub
Function DecryptTextFromFile(ByVal FileName As String, ByVal Key() As Byte, ByVal IV() As Byte) As String
Try
Dim fStream As FileStream = File.Open(FileName, FileMode.OpenOrCreate)
Dim RC2alg As RC2 = RC2.Create
Dim cStream As New CryptoStream(fStream, RC2alg.CreateDecryptor(Key, IV), CryptoStreamMode.Read)
Dim sReader As New StreamReader(cStream)
Dim val As String = sReader.ReadLine()
sReader.Close()
cStream.Close()
fStream.Close()
Return val
Catch e As CryptographicException
Console.WriteLine("A Cryptographic error occurred: {0}", e.Message)
Return Nothing
Catch e As UnauthorizedAccessException
Console.WriteLine("A file error occurred: {0}", e.Message)
Return Nothing
End Try
End Function
End Module
4. The Encrypted file is store where the project is saved.