Public Function Encrypt(ByVal plainText As String) As String 
    'portare fuori dalla funzione 
    Dim passPhrase As String = "p@ssPhra$e"    ' puo essere qualsiasi stringa 
    Dim saltValue As String = "bla-bla$2007"  ' puo essere qualsiasi stringa 
    Dim hashAlgorithm As String = "SHA1"       ' puo anche essere "MD5" 
    Dim passwordIterations As Integer = 2          ' puo essere qualsiasi numero 
    Dim initVector As String = "@12BCD34E5F6G78H" ' deve essere 16 bytes 
    Dim keySize As Integer = 256        ' puo anche essere 192 or 128 
    'portare fuori dalla funzione 
    Dim initVectorBytes As Byte() = Encoding.ASCII.GetBytes(initVector) 
    Dim saltValueBytes As Byte() = Encoding.ASCII.GetBytes(saltValue) 
    Dim plainTextBytes As Byte() = Encoding.UTF8.GetBytes(plainText) 
    Dim password As PasswordDeriveBytes = New PasswordDeriveBytes(passPhrase, saltValueBytes, hashAlgorithm, passwordIterations) 
    Dim keyBytes As Byte() = password.GetBytes(keySize / 8) 
    Dim symmetricKey As RijndaelManaged = New RijndaelManaged() 
    symmetricKey.Mode = CipherMode.CBC 
    Dim encryptor As ICryptoTransform = symmetricKey.CreateEncryptor(keyBytes, initVectorBytes) 
    Dim memoryStream As MemoryStream = New MemoryStream() 
    Dim cryptoStream As CryptoStream = New CryptoStream(memoryStream, encryptor, CryptoStreamMode.Write) 
    cryptoStream.Write(plainTextBytes, 0, plainTextBytes.Length) 
    cryptoStream.FlushFinalBlock() 
    Dim cipherTextBytes As Byte() = memoryStream.ToArray() 
    memoryStream.Close() 
    cryptoStream.Close() 
    Dim cipherText As String = Convert.ToBase64String(cipherTextBytes) 
    Return cipherText 
  End Function 

  Public Function Decrypt(ByVal cipherText As String) As String 

    'portare fuori dalla funzione 
    Dim passPhrase As String = "p@ssPhra$e"     ' can be any string 
    Dim saltValue As String = "bla-bla$2007" ' can be any string 
    Dim hashAlgorithm As String = "SHA1"       ' can be "MD5" 
    Dim passwordIterations As Integer = 2         ' can be any number 
    Dim initVector As String = "@12BCD34E5F6G78H" ' must be 16 bytes 
    Dim keySize As Integer = 256        ' can be 192 or 128 
    'fino qui 
    Dim initVectorBytes As Byte() = Encoding.ASCII.GetBytes(initVector) 
    Dim saltValueBytes As Byte() = Encoding.ASCII.GetBytes(saltValue) 
    Dim cipherTextBytes As Byte() = Convert.FromBase64String(cipherText) 
    Dim password As PasswordDeriveBytes = New PasswordDeriveBytes(passPhrase, saltValueBytes, hashAlgorithm, passwordIterations) 
    Dim keyBytes As Byte() = password.GetBytes(keySize / 8) 
    Dim symmetricKey As RijndaelManaged = New RijndaelManaged() 
    symmetricKey.Mode = CipherMode.CBC 
    Dim decryptor As ICryptoTransform = symmetricKey.CreateDecryptor(keyBytes, initVectorBytes) 
    Dim memoryStream As MemoryStream 
    memoryStream = New MemoryStream(cipherTextBytes) 
    Dim cryptoStream As CryptoStream = New CryptoStream(memoryStream, decryptor, CryptoStreamMode.Read) 
    Dim plainTextBytes As Byte() 
    ReDim plainTextBytes(cipherTextBytes.Length) 
    Dim decryptedByteCount As Integer 
    decryptedByteCount = cryptoStream.Read(plainTextBytes, 0, plainTextBytes.Length) 
    memoryStream.Close() 
    cryptoStream.Close() 
    Dim plainText As String 
    plainText = Encoding.UTF8.GetString(plainTextBytes, 0, decryptedByteCount) 
    Decrypt = plainText 
End Function