Check out example codes for "get address from latitude and longitude in swift". It will help you in understanding the concepts better.

Code Example 1

func getAddressFromLatLon(pdblLatitude: String, withLongitude pdblLongitude: String) {
        var center : CLLocationCoordinate2D = CLLocationCoordinate2D()
        let lat: Double = Double("\(pdblLatitude)")!
        //21.228124
        let lon: Double = Double("\(pdblLongitude)")!
        //72.833770
        let ceo: CLGeocoder = CLGeocoder()
        center.latitude = lat
        center.longitude = lon

        let loc: CLLocation = CLLocation(latitude:center.latitude, longitude: center.longitude)


        ceo.reverseGeocodeLocation(loc, completionHandler:
            {(placemarks, error) in
                if (error != nil)
                {
                    print("reverse geodcode fail: \(error!.localizedDescription)")
                }
                let pm = placemarks! as [CLPlacemark]

                if pm.count > 0 {
                    let pm = placemarks![0]
                    print(pm.country)
                    print(pm.locality)
                    print(pm.subLocality)
                    print(pm.thoroughfare)
                    print(pm.postalCode)
                    print(pm.subThoroughfare)
                    var addressString : String = ""
                    if pm.subLocality != nil {
                        addressString = addressString + pm.subLocality! + ", "
                    }
                    if pm.thoroughfare != nil {
                        addressString = addressString + pm.thoroughfare! + ", "
                    }
                    if pm.locality != nil {
                        addressString = addressString + pm.locality! + ", "
                    }
                    if pm.country != nil {
                        addressString = addressString + pm.country! + ", "
                    }
                    if pm.postalCode != nil {
                        addressString = addressString + pm.postalCode! + " "
                    }


                    print(addressString)
              }
        })

    }

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