Swift 4 macOS App - How to find the important users directories?

Question

What is the easiest way with Swift 4 for a macOS application to find the important users directories like: Desktop, Documents, Downloads etc.?

Answer 1

TLDR:

let desktopDir = try? FileManager.default.url(for: .desktopDirectory, in: .userDomainMask, appropriateFor: nil, create: false)
let documentDir = try? FileManager.default.url(for: .documentDirectory, in: .userDomainMask, appropriateFor: nil, create: false)
let downloadsDir = try? FileManager.default.url(for: .downloadsDirectory, in: .userDomainMask, appropriateFor: nil, create: false)

---

There are two methods to get this information, both from the FileManager class:

This one:

func urls(for directory: FileManager.SearchPathDirectory, 
   in domainMask: FileManager.SearchPathDomainMask) -> [URL]

Returns an array of URLs for the specified common directory in the requested domains. […] The directories are ordered according to the order of the domain mask constants, with items in the user domain first and items in the system domain last.

Documentation: https://developer.apple.com/documentation/foundation/filemanager/1407726-urls

(already mentioned in @leo-dabus' answer)

And this one:

(which I prefer since it's more versatile and returns a single URL)

func url(for directory: FileManager.SearchPathDirectory, 
  in domain: FileManager.SearchPathDomainMask, 
  appropriateFor url: URL?, 
  create shouldCreate: Bool) throws -> URL

Locates and optionally creates the specified common directory in a domain.

Documentation: https://developer.apple.com/documentation/foundation/filemanager/1407693-url

For either one:

The valid domains, defined in https://developer.apple.com/documentation/foundation/filemanager.searchpathdomainmask are:

.userDomainMask: The user’s home directory—the place to install user’s personal items (~).

.localDomainMask: Local to the current machine—the place to install items available to everyone on this machine.

.networkDomainMask: Publicly available location in the local area network—the place to install items available on the network (/Network).

.systemDomainMask: Provided by Apple—can’t be modified (/System) .

.allDomainsMask: All domains.

There are lots of possibilities for the directory parameter, defined in https://developer.apple.com/documentation/foundation/filemanager.searchpathdirectory :

.applicationDirectory: Supported applications (/Applications).

.demoApplicationDirectory: Unsupported applications and demonstration versions.

.developerApplicationDirectory: Developer applications (/Developer/Applications).

.adminApplicationDirectory System and network administration applications.

.libraryDirectory: Various user-visible documentation, support, and configuration files (/Library).

.developerDirectory: Developer resources (/Developer).

.userDirectory: User home directories (/Users).

.documentationDirectory: Documentation.

.documentDirectory: Document directory.

.coreServiceDirectory: Location of core services (System/Library/CoreServices).

.autosavedInformationDirectory: Location of user’s autosaved documents (Library/Autosave Information).

.desktopDirectory: Location of user’s desktop directory.

.cachesDirectory: Location of discardable cache files (Library/Caches).

.applicationSupportDirectory: Location of application support files (Library/Application Support).

.downloadsDirectory: Location of the user’s downloads directory.

.inputMethodsDirectory: Location of Input Methods (Library/Input Methods).

.moviesDirectory: Location of user's Movies directory (~/Movies).

.musicDirectory: Location of user's Music directory (~/Music).

.picturesDirectory: Location of user's Pictures directory (~/Pictures).

.printerDescriptionDirectory: Location of system's PPDs directory (Library/Printers/PPDs).

.sharedPublicDirectory: Location of user's Public sharing directory (~/Public).

.preferencePanesDirectory: Location of the PreferencePanes directory for use with System Preferences (Library/PreferencePanes).

.applicationScriptsDirectory: Location of the user scripts folder for the calling application (~/Library/Application Scripts/),

.itemReplacementDirectory: Passed to the FileManager method url(for:in:appropriateFor:create:) in order to create a temporary directory.

.allApplicationsDirectory: All directories where applications can occur.

.allLibrariesDirectory: All directories where resources can occur.

.trashDirectory: Location of the trash directory.