Imports System.Security.Cryptography
Imports System.Text
Imports System.IO
Module DESCSPSample
Sub Main()
Dim DESalg As New DESCryptoServiceProvider
Dim sData As String = "this is a test"
Dim FileName As String = "data.txt"
EncryptTextToFile(sData, FileName, DESalg.Key, DESalg.IV)
Dim Final As String = DecryptTextFromFile(FileName, DESalg.Key, DESalg.IV)
Console.WriteLine(Final)
End Sub
Sub EncryptTextToFile(ByVal Data As String, ByVal FileName As String, ByVal Key() As Byte, ByVal IV() As Byte)
Dim fStream As FileStream = File.Open(FileName, FileMode.OpenOrCreate)
Dim cStream As New CryptoStream(fStream,New DESCryptoServiceProvider().CreateEncryptor(Key, IV),CryptoStreamMode.Write)
Dim sWriter As New StreamWriter(cStream)
sWriter.WriteLine(Data)
sWriter.Close()
cStream.Close()
fStream.Close()
End Sub
Function DecryptTextFromFile(ByVal FileName As String, ByVal Key() As Byte, ByVal IV() As Byte) As String
Dim fStream As FileStream = File.Open(FileName, FileMode.OpenOrCreate)
Dim cStream As New CryptoStream(fStream,New DESCryptoServiceProvider().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
End Function
End Module
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