Xbase++

Generating Repeatable Random Data for Testing/Debugging

See more PRNG Examples

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

LOCAL nSuccess
LOCAL oFortuna
LOCAL cStrRandHex
LOCAL cStrRandBase64
LOCAL cStrRandBase58
LOCAL oFortuna2

nSuccess := 0

//  This example assumes the Chilkat API to have been previously unlocked.
//  See Global Unlock Sample for sample code.

nSuccess := 0

oFortuna := CreateObject("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.
nSuccess := oFortuna:AddEntropy("01020304", "hex")
nSuccess := oFortuna:AddEntropy("hello world", "ascii")

//  Generate some random data:
cStrRandHex := oFortuna:GenRandom(16, "hex")
cStrRandBase64 := oFortuna:GenRandom(22, "base64")
cStrRandBase58 := oFortuna:GenRandom(32, "base58")

? "hex random bytes: " + cStrRandHex
? "base64 random bytes: " + cStrRandBase64
? "base58 random bytes: " + cStrRandBase58

//  Try it again with a different object to verify that the same results are obtained:
oFortuna2 := CreateObject("Chilkat.Prng")

nSuccess := oFortuna2:AddEntropy("01020304", "hex")
nSuccess := oFortuna2:AddEntropy("hello world", "ascii")

cStrRandHex := oFortuna2:GenRandom(16, "hex")
cStrRandBase64 := oFortuna2:GenRandom(22, "base64")
cStrRandBase58 := oFortuna2:GenRandom(32, "base58")

? "hex random bytes: " + cStrRandHex
? "base64 random bytes: " + cStrRandBase64
? "base58 random bytes: " + cStrRandBase58

oFortuna:destroy()
oFortuna2:destroy()