how to zoom-in on the Mapkit by swift

 @IBAction func zoomInMap (sender: AnyObject) {

        let userLocation = mapView.userLocation

        let region = MKCoordinateRegionMakeWithDistance(userLocation.location!.coordinate, 800, 800)

        mapView.setRegion(region,animated:true)

    }

connect with action "zoomInMap"

set the parameter in MKCoordinateRegionMakeWithDistance property.