I ride in work clothes, usually under full rain gear (jacket, pants, booties, gloves, everything), with bike shoes.
I take it a bit easy on the way in and don't get soaked with perspiration, I'm not a big sweat-er which helps, and I have a fan in my office to cool myself down if I did ride kind of hard.
On the way home, I ride hard, get all sweaty, and don't care.
There is a mini-gym at work with a locker room and showers, so I could change, but I have to be in at 5:30 AM, so I'd rather sleep longer.