The driver of a vehicle within a business or residence district emerging from an alley, driveway or building shall stop such vehicle immediately prior to driving onto a sidewalk or onto the sidewalk area extending across any alleyway or driveway, and shall yield the right of way to any pedestrian as may be necessary to avoid collision, and upon entering the roadway shall yield the right of way to all vehicles approaching on said roadway. (1960 Code, Sec. 7-1204)