Create and use an RC2 object to encrypt and decrypt data in memory. : RC2 « Security « VB.Net Tutorial

1. VB.Net Tutorial
2. Security
3. RC2

Imports System.Security.Cryptography
Imports System.Text
Imports System.IO

Module RC2PSample

    Sub Main()
        Try
            Dim RC2alg As RC2 = RC2.Create("RC2")
            Dim sData As String = "this is a test."
            Dim Data As Byte() = EncryptTextToMemory(sData, RC2alg.Key, RC2alg.IV)
            Dim Final As String = DecryptTextFromMemory(Data, RC2alg.Key, RC2alg.IV)
            Console.WriteLine(Final)
        Catch e As Exception
            Console.WriteLine(e.Message)
        End Try
    End Sub
    Function EncryptTextToMemory(ByVal Data As String, ByVal Key() As Byte, ByVal IV() As Byte) As Byte()
        Try
            Dim mStream As New MemoryStream
            Dim RC2alg As RC2 = RC2.Create
            Dim cStream As New CryptoStream(mStream,RC2alg.CreateEncryptor(Key, IV),CryptoStreamMode.Write)
            Dim toEncrypt As Byte() = New ASCIIEncoding().GetBytes(Data)
            cStream.Write(toEncrypt, 0, toEncrypt.Length)
            cStream.FlushFinalBlock()
            Dim ret As Byte() = mStream.ToArray()
            cStream.Close()
            mStream.Close()
            Return ret
        Catch e As CryptographicException
            Console.WriteLine("A Cryptographic error occurred: {0}", e.Message)
            Return Nothing
        End Try
    End Function
    Function DecryptTextFromMemory(ByVal Data() As Byte, ByVal Key() As Byte, ByVal IV() As Byte) As String
        Try
            Dim msDecrypt As New MemoryStream(Data)
            Dim RC2alg As RC2 = RC2.Create
            Dim csDecrypt As New CryptoStream(msDecrypt,RC2alg.CreateDecryptor(Key, IV),CryptoStreamMode.Read)
            Dim fromEncrypt(Data.Length) As Byte
            csDecrypt.Read(fromEncrypt, 0, fromEncrypt.Length)
            Return New ASCIIEncoding().GetString(fromEncrypt)
        Catch e As CryptographicException
            Console.WriteLine("A Cryptographic error occurred: {0}", e.Message)
            Return Nothing
        End Try
    End Function
End Module