Yeah I agree with most of the folks here. Depends on the type of heels and shorts. If you wear with super short shorts with super high heels, that's super trashy! Choose a nice pair of strappy or wedge heel footwear. It would also help if you bring equal attention to you upper half. Add a touch of class to your outfit by keeping it layered - a smart coat or jacket would help. And I think denim shorts are out, it's time to move on to other ones!
Well it could go either way really, If the shorts are tight & way too small that your ass checks are hangging out, yeah trasy. But if your wearing a nice pari or shorts that at least cover half of your thighs & your ass & lips are showing, I would say WOW! but it really depends on the shorts really. do ya wanna look like a slut, or a model ? your choice.