VB Forum / General 2 / June 2004

The routine relies on the repeatability of random numbers, so seeding
with -4 provides for predicable decoding when passing the string back
through the same routine. It falls apart when a truly random number is
generated for the encode and decode sequences preventing the decoding from
working.  The reason it *appears* to work if you use your suggestion just
for this demo is that the Timer function seeds the number to the time of the
machine, and as the code executes very quickly both the encoding and
decoding are happening at the same Timer time.  If you try this modification
to the Command1_Click routine to introduce a delay when your
suggested -(Timer) is used instead of -4, you'll see the results are not as
you'd expect. Restoring to -4 (or any other fixed number for that matter)
will work...

Private Declare Sub Sleep Lib "kernel32" (ByVal dwMilliseconds As Long)

Private Sub Command1_Click()

  Me.AutoRedraw = True

  Dim sEncodedEmail As String

  Print
  Print Command1.Caption

  sEncodedEmail = ConvertData(sDummyEmail)
  Print "encoded", sEncodedEmail
  Refresh
  Call Sleep(1000)  'wait 1 second before decoding
  Print "decoded", ConvertData(sEncodedEmail)

End Sub