Obtendo a lista de arquivos na pasta de documentos

O que há de errado com meu código para obter os nomes de arquivos na pasta do documento?

func listFilesFromDocumentsFolder() -> [NSString]?{
    var theError = NSErrorPointer()
    let dirs = NSSearchPathForDirectoriesInDomains(NSSearchPathDirectory.DocumentDirectory, NSSearchPathDomainMask.AllDomainsMask, true) as? [String]
    if dirs != nil {
        let dir = dirs![0] as NSString
        let fileList = NSFileManager.defaultManager().contentsOfDirectoryAtPath(dir, error: theError) as [NSString]
        return fileList
    }else{
        return nil
    }
}

Pensei ter lido os documentos corretamente e tenho certeza do que está na pasta de documentos, mas "fileList" não mostra nada? "dir" mostra o caminho para a pasta.

Esta solução funciona com o Swift 4 (Xcode 9.2) e também com o Swift 5 (Xcode 10.2.1+):

let fileManager = FileManager.default
let documentsURL = fileManager.urls(for: .documentDirectory, in: .userDomainMask)[0]
do {
    let fileURLs = try fileManager.contentsOfDirectory(at: documentsURL, includingPropertiesForKeys: nil)
    // process files
} catch {
    print("Error while enumerating files \(documentsURL.path): \(error.localizedDescription)")
}

Aqui está uma extensão reutilizável do FileManager que também permite ignorar ou incluir arquivos ocultos nos resultados:

import Foundation

extension FileManager {
    func urls(for directory: FileManager.SearchPathDirectory, skipsHiddenFiles: Bool = true ) -> [URL]? {
        let documentsURL = urls(for: directory, in: .userDomainMask)[0]
        let fileURLs = try? contentsOfDirectory(at: documentsURL, includingPropertiesForKeys: nil, options: skipsHiddenFiles ? .skipsHiddenFiles : [] )
        return fileURLs
    }
}

// Usage
print(FileManager.default.urls(for: .documentDirectory) ?? "none")

Swift 5

// Get the document directory url
let documentsUrl =  FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first!

do {
    // Get the directory contents urls (including subfolders urls)
    let directoryContents = try FileManager.default.contentsOfDirectory(at: documentsUrl, includingPropertiesForKeys: nil)
    print(directoryContents)

    // if you want to filter the directory contents you can do like this:
    let mp3Files = directoryContents.filter{ $0.pathExtension == "mp3" }
    print("mp3 urls:",mp3Files)
    let mp3FileNames = mp3Files.map{ $0.deletingPathExtension().lastPathComponent }
    print("mp3 list:", mp3FileNames)

} catch {
    print(error)
}

Uma sintaxe mais curta para SWIFT 3

func listFilesFromDocumentsFolder() -> [String]?
{
    let fileMngr = FileManager.default;

    // Full path to documents directory
    let docs = fileMngr.urls(for: .documentDirectory, in: .userDomainMask)[0].path

    // List all contents of directory and return as [String] OR nil if failed
    return try? fileMngr.contentsOfDirectory(atPath:docs)
}

Exemplo de uso:

override func viewDidLoad()
{
    print(listFilesFromDocumentsFolder())
}

Testado no xCode 8.2.3 para iPhone 7 com iOS 10.2 e iPad com iOS 9.3

A Apple declara sobre NSSearchPathForDirectoriesInDomains(_:_:_:):

Você deve considerar o uso dos FileManagermétodos urls(for:in:)e url(for:in:appropriateFor:create:)quais URLs de retorno, que são o formato preferido.

Com o Swift 5, FileManagertem um método chamado contentsOfDirectory(at:includingPropertiesForKeys:options:). contentsOfDirectory(at:includingPropertiesForKeys:options:)tem a seguinte declaração:

Executa uma pesquisa superficial do diretório especificado e retorna URLs para os itens contidos.

func contentsOfDirectory(at url: URL, includingPropertiesForKeys keys: [URLResourceKey]?, options mask: FileManager.DirectoryEnumerationOptions = []) throws -> [URL]

Portanto, para recuperar os URLs dos arquivos contidos no diretório de documentos, você pode usar o seguinte snippet de código que usa FileManager's urls(for:in:)e contentsOfDirectory(at:includingPropertiesForKeys:options:)métodos:

guard let documentsDirectory = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first else { return }

do {
    let directoryContents = try FileManager.default.contentsOfDirectory(at: documentsDirectory, includingPropertiesForKeys: nil, options: [])

    // Print the urls of the files contained in the documents directory
    print(directoryContents)
} catch {
    print("Could not search for urls of files in documents directory: \(error)")
}

Como exemplo, a UIViewControllerimplementação abaixo mostra como salvar um arquivo do pacote de aplicativos no diretório de documentos e como obter os URLs dos arquivos salvos no diretório de documentos:

import UIKit

class ViewController: UIViewController {

    @IBAction func copyFile(_ sender: UIButton) {
        // Get file url
        guard let fileUrl = Bundle.main.url(forResource: "Movie", withExtension: "mov") else { return }

        // Create a destination url in document directory for file
        guard let documentsDirectory = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first else { return }
        let documentDirectoryFileUrl = documentsDirectory.appendingPathComponent("Movie.mov")

        // Copy file to document directory
        if !FileManager.default.fileExists(atPath: documentDirectoryFileUrl.path) {
            do {
                try FileManager.default.copyItem(at: fileUrl, to: documentDirectoryFileUrl)
                print("Copy item succeeded")
            } catch {
                print("Could not copy file: \(error)")
            }
        }
    }

    @IBAction func displayUrls(_ sender: UIButton) {
        guard let documentsDirectory = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first else { return }

        do {
            let directoryContents = try FileManager.default.contentsOfDirectory(at: documentsDirectory, includingPropertiesForKeys: nil, options: [])

            // Print the urls of the files contained in the documents directory
            print(directoryContents) // may print [] or [file:///private/var/mobile/Containers/Data/Application/.../Documents/Movie.mov]
        } catch {
            print("Could not search for urls of files in documents directory: \(error)")
        }
    }

}

Este código imprime todos os diretórios e arquivos no meu diretório de documentos:

Alguma modificação de sua função:

func listFilesFromDocumentsFolder() -> [String]
{
    let dirs = NSSearchPathForDirectoriesInDomains(FileManager.SearchPathDirectory.documentDirectory, FileManager.SearchPathDomainMask.allDomainsMask, true)
    if dirs != [] {
        let dir = dirs[0]
        let fileList = try! FileManager.default.contentsOfDirectory(atPath: dir)
        return fileList
    }else{
        let fileList = [""]
        return fileList
    }
}

Qual é chamado por:

    let fileManager:FileManager = FileManager.default
    let fileList = listFilesFromDocumentsFolder()

    let count = fileList.count

    for i in 0..<count
    {
        if fileManager.fileExists(atPath: fileList[i]) != true
        {
            print("File is \(fileList[i])")
        }
    }

Compatibilidade com Swift 2.0

func listWithFilter () {

    let fileManager = NSFileManager.defaultManager()
           // We need just to get the documents folder url
    let documentsUrl = fileManager.URLsForDirectory(.DocumentDirectory, inDomains: .UserDomainMask)[0] as NSURL

    do {
    // if you want to filter the directory contents you can do like this:
    if let directoryUrls = try? NSFileManager.defaultManager().contentsOfDirectoryAtURL(documentsUrl, includingPropertiesForKeys: nil, options: NSDirectoryEnumerationOptions.SkipsSubdirectoryDescendants) {
        print(directoryUrls)
       ........
        }

    }

}

OU

 func listFiles() -> [String] {

    var theError = NSErrorPointer()
    let dirs = NSSearchPathForDirectoriesInDomains(NSSearchPathDirectory.DocumentDirectory, NSSearchPathDomainMask.AllDomainsMask, true) as? [String]
    if dirs != nil {
        let dir = dirs![0]
        do {
        let fileList = try NSFileManager.defaultManager().contentsOfDirectoryAtPath(dir)
        return fileList as [String]
        }catch {

        }

    }else{
        let fileList = [""]
        return fileList
    }
    let fileList = [""]
    return fileList

}

Solução simples e dinâmica (Swift 5):

extension FileManager {

  class func directoryUrl() -> URL? {
      let paths = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)
      return paths.first
  }

  class func allRecordedData() -> [URL]? {
     if let documentsUrl = FileManager.directoryUrl() {
        do {
            let directoryContents = try FileManager.default.contentsOfDirectory(at: documentsUrl, includingPropertiesForKeys: nil)
            return directoryContents.filter{ $0.pathExtension == "m4a" }
        } catch {
            return nil
        }
     }
     return nil
  }}