Transfer Pokemon save file between emulator rom and real console?

Ok so I have been looking for the answer for so long, many people tell me it's not possible, many people tell me it is.

If I use a GBA emulator on a computer such as VBA to play ROMS of Pokemon Emerald for example.

Can I then perhaps with the use of flash cards, transfer my save and carry on playing on a real GBA or preferably, a DS lite? I am willing to go to great legnths and spend a lot of money if need be.

Thanks everyone.