Look, there's no easy way to say this - you're screwed. If you accept freeform input from the web, you have to live with the reality that people around the world format dates differently. That's why so many websites use popup calendars, and such, to get user input. No ambiguity there. No matter what you think, .NET's library routines can't fathom your user's intentions any better than any other library.
Fwiw, the code Mike posted is absolutely VB6. I'm not sure what about it looks like VB.NET? Once you get a date/time into a Date variable, you can display it however you want with Format(). That's the easy part.
I'd strongly suggest you either A) find a way to gather your inputs unambiguously, or B) tell your users what format you expect and live with what they input. All that said, is it possible I misunderstood the question, and you really do know what format the user is providing the data in? (Because if so, I really am having trouble understanding what's the problem interpreting it in ClassicVB - sorry.)
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