Check if location services are enabled

Add the CLLocationManagerDelegate to your class inheritance and then you can make this check:

Import CoreLocation Framework

import CoreLocation

Swift 1.x – 2.x version:

if CLLocationManager.locationServicesEnabled() {
    switch CLLocationManager.authorizationStatus() {
    case .NotDetermined, .Restricted, .Denied:
        print("No access")
    case .AuthorizedAlways, .AuthorizedWhenInUse:
        print("Access")
    }
} else {
    print("Location services are not enabled")
}

Swift 4.x version:

if CLLocationManager.locationServicesEnabled() {
     switch CLLocationManager.authorizationStatus() {
        case .notDetermined, .restricted, .denied:
            print("No access")
        case .authorizedAlways, .authorizedWhenInUse:
            print("Access")
     }
} else {
    print("Location services are not enabled")
}

Swift 5.1 version

if CLLocationManager.locationServicesEnabled() {
    switch CLLocationManager.authorizationStatus() {
        case .notDetermined, .restricted, .denied:
            print("No access")
        case .authorizedAlways, .authorizedWhenInUse:
            print("Access")
        @unknown default:
            break
    }
} else {
    print("Location services are not enabled")
}

iOS 14.x

In iOS 14 you will get the following error message:
authorizationStatus() was deprecated in iOS 14.0

To solve this, use the following:

private let locationManager = CLLocationManager()

if CLLocationManager.locationServicesEnabled() {
    switch locationManager.authorizationStatus {
        case .notDetermined, .restricted, .denied:
            print("No access")
        case .authorizedAlways, .authorizedWhenInUse:
            print("Access")
        @unknown default:
            break
    }
} else {
    print("Location services are not enabled")
}