Here are the simplest, most effective solutions (as usual).
CryptBytes is a simple-to-use codec class will Compress, Encrypt, and URL Encode binary data into a text string that can be simply stored in a database or sent through the Internet.
RC4 is fast and simple to hide data from casual browsers.
RC6 is short, rare and good and capable of keeping data safe.
Scrambler.h contains several routines and classes that will reverse, interleave and scramble bits in a DWORD or turn them to text and back.
They are most useful for creating and manipulating keys for higher levels of encryption or for license and serial codes etc.
Mix them all together various times in various ways with plenty of calls to Rand and you'll soon have well muddled data that can only be restored by reversing whatever it was that you did!
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