I have a commercial building I rent in the downtown area of my town.
So the city has came in and put Christmas ( OK "holiday" lights ) on the top edge of all of the buildings, The entire downtown area.

I am OK with it, since I will add tons more to my building, but what if I did not want it, would the city have the right to put lights on my building without permission or asking.

You would want to consider the negative publicity in fighting it.
Also, who's providing the power for these lights?

The city council probably passed an ordinance allowing them to decorate the commercial buildings for holidays. If they did so, and as long as the decorations weren't discriminatory, it would be legal and the building owner's permission wouldn't be required.