What is the difference between a municipality's exercise of zoning power and the right of the municipality to issue a building permit?

Though appellants are correct when they state that '[t]here is a dichotomy to be recognized between the exercise of the zoning power, as such, and the right of the municipality to issue a building permit,' they forget that the right to issue or not to issue a building permit depends on the zoning ordinance. Furthermore, it is clear that the zoning function also involves the police power. (Euclid v. Ambler Co., 272 U.S. 365, 47 S.Ct. 144, 71 L.Ed. 303.) That the ordinance in question involves the police power does not mean that the ordinance in question is not a zoning ordinance.