Sweating and smelling are two different things. If you smell when you sweat, then take the suggestions below. But if you want to stop sweating period, then that is not only unwise but unhealthy.
You sweat for a reason. #1 is for your body not to overheat and to cool itself. #2, it flushes toxins out of your body. I would recommend shirts that hide the sweat or wear pit covers that attach to your shirt that absorb the sweat.
If there is an odor problem, that is the result of bacteria growing in those areas and that can be reduced by eating healthier, especially yogurt and such.