(VB.NET) Generating Repeatable Random Data for Testing/Debugging

Demonstrates how to use the Fortuna PRNG to generate random-looking but repeatable non-random data for the purpose of testing and debugging.

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' All Chilkat classes can be unlocked at once at the beginning of a program
' by calling UnlockBundle.  It requires a Bundle unlock code.
Dim chilkatGlob As New Chilkat.Global
Dim success As Boolean = chilkatGlob.UnlockBundle("Anything for 30-day trial.")
If (success <> True) Then
    Debug.WriteLine(chilkatGlob.LastErrorText)
    Exit Sub
End If


Dim fortuna As New Chilkat.Prng

' Normally an application would seed the PRNG with entropy from
' some real random source.  However, sometimes we want the same
' random sequence of bytes for testing and debugging purposes.
' This a reason why GetEntropy and AddEntropy are two different methods.
' An application could omit the call to GetEntropy, and instead pass
' non-random data to AddEntropy. For example:

' Seed the PRNG with non-entropy, so we get a repeatable sequence.
' Note: AddEntropy can be called any number of times.
success = fortuna.AddEntropy("01020304","hex")
success = fortuna.AddEntropy("hello world","ascii")

' Generate some random data:
Dim strRandHex As String = fortuna.GenRandom(16,"hex")
Dim strRandBase64 As String = fortuna.GenRandom(22,"base64")
Dim strRandBase58 As String = fortuna.GenRandom(32,"base58")

Debug.WriteLine("hex random bytes: " & strRandHex)
Debug.WriteLine("base64 random bytes: " & strRandBase64)
Debug.WriteLine("base58 random bytes: " & strRandBase58)


' Try it again with a different object to verify that the same results are obtained:
Dim fortuna2 As New Chilkat.Prng

success = fortuna2.AddEntropy("01020304","hex")
success = fortuna2.AddEntropy("hello world","ascii")

strRandHex = fortuna2.GenRandom(16,"hex")
strRandBase64 = fortuna2.GenRandom(22,"base64")
strRandBase58 = fortuna2.GenRandom(32,"base58")

Debug.WriteLine("hex random bytes: " & strRandHex)
Debug.WriteLine("base64 random bytes: " & strRandBase64)
Debug.WriteLine("base58 random bytes: " & strRandBase58)