I'm quite new to programming a Swift and I'm trying to iterate through the files in a folder.
I took a look at the answer here and tried to translate it to Swift syntax, but didn't succeed.
let fileManager = NSFileManager.defaultManager()
let enumerator:NSDirectoryEnumerator = fileManager.enumeratorAtPath(folderPath)
for element in enumerator {
//do something
}
the error I get is:
Type 'NSDirectoryEnumerator' does not conform to protocol 'SequenceType'
My aim is to look at all the subfolders and files contained into the main folder and find all the files with a certain extension to then do something with them.
Use the nextObject() method of enumerator:
while let element = enumerator?.nextObject() as? String {
if element.hasSuffix("ext") { // checks the extension
}
}
Nowadays (early 2017) it's highly recommended to use the – more versatile – URL related API
let fileManager = FileManager.default
do {
let resourceKeys : [URLResourceKey] = [.creationDateKey, .isDirectoryKey]
let documentsURL = try fileManager.url(for: .documentDirectory, in: .userDomainMask, appropriateFor: nil, create: false)
let enumerator = FileManager.default.enumerator(at: documentsURL,
includingPropertiesForKeys: resourceKeys,
options: [.skipsHiddenFiles], errorHandler: { (url, error) -> Bool in
print("directoryEnumerator error at \(url): ", error)
return true
})!
for case let fileURL as URL in enumerator {
let resourceValues = try fileURL.resourceValues(forKeys: Set(resourceKeys))
print(fileURL.path, resourceValues.creationDate!, resourceValues.isDirectory!)
}
} catch {
print(error)
}
I couldn't get pNre's solution to work at all; the while loop just never received anything. However, I did come across this solution which works for me (in Xcode 6 beta 6, so perhaps things have changed since pNre posted the above answer?):
for url in enumerator!.allObjects {
print("\((url as! NSURL).path!)")
}
my two cents from previously anwers.. more swifty and with optionals:
let enumerator = FileManager.default.enumerator(atPath: folderPath)
while let element = enumerator?.nextObject() as? String {
print(element)
if let fType = enumerator?.fileAttributes?[FileAttributeKey.type] as? FileAttributeType{
switch fType{
case .typeRegular:
print("a file")
case .typeDirectory:
print("a dir")
}
}
}
returns all files in a directory + in subdirectories
import Foundation
let path = "<some path>"
let enumerator = FileManager.default.enumerator(atPath: path)
while let filename = enumerator?.nextObject() as? String {
print(filename)
}
Swift3 + absolute urls
extension FileManager {
func listFiles(path: String) -> [URL] {
let baseurl: URL = URL(fileURLWithPath: path)
var urls = [URL]()
enumerator(atPath: path)?.forEach({ (e) in
guard let s = e as? String else { return }
let relativeURL = URL(fileURLWithPath: s, relativeTo: baseurl)
let url = relativeURL.absoluteURL
urls.append(url)
})
return urls
}
}
Based on code from #user3441734
Swift 3
let fd = FileManager.default
fd.enumerator(atPath: "/Library/FileSystems")?.forEach({ (e) in
if let e = e as? String, let url = URL(string: e) {
print(url.pathExtension)
}
})
In case that you are getting the
'NSDirectoryEnumerator?' does not have a member named 'nextObject' error
the while loop should be:
while let element = enumerator?.nextObject() as? String {
// do things with element
}
It has something to do with optional chaining
SWIFT 3.0
Returns all files with extension in the Directory passed & its subdirectories
func extractAllFile(atPath path: String, withExtension fileExtension:String) -> [String] {
let pathURL = NSURL(fileURLWithPath: path, isDirectory: true)
var allFiles: [String] = []
let fileManager = FileManager.default
let pathString = path.replacingOccurrences(of: "file:", with: "")
if let enumerator = fileManager.enumerator(atPath: pathString) {
for file in enumerator {
if #available(iOS 9.0, *) {
if let path = NSURL(fileURLWithPath: file as! String, relativeTo: pathURL as URL).path, path.hasSuffix(".\(fileExtension)"){
let fileNameArray = (path as NSString).lastPathComponent.components(separatedBy: ".")
allFiles.append(fileNameArray.first!)
}
} else {
// Fallback on earlier versions
print("Not available, #available iOS 9.0 & above")
}
}
}
return allFiles
}
Updating for Swift 3:
let fileManager = FileManager() // let fileManager = NSFileManager.defaultManager()
let en=fileManager.enumerator(atPath: the_path) // let enumerator:NSDirectoryEnumerator = fileManager.enumeratorAtPath(folderPath)
while let element = en?.nextObject() as? String {
if element.hasSuffix("ext") {
// do something with the_path/*.ext ....
}
}
Adding to vadian's response -- the Apple docs mention that Path-based URLs are simpler in some ways, however file reference URLs have the advantage that the reference remains valid if the file is moved or renamed while your app is running.
From the documentation for "Accessing Files and Directories":
"Path-based URLs are easier to manipulate, easier to debug, and are generally preferred by classes such as NSFileManager. An advantage of file reference URLs is that they are less fragile than path-based URLs while your app is running. If the user moves a file in the Finder, any path-based URLs that refer to the file immediately become invalid and must be updated to the new path. However, as long as the file moved to another location on the same disk, its unique ID does not change and any file reference URLs remain valid."
https://developer.apple.com/library/content/documentation/FileManagement/Conceptual/FileSystemProgrammingGuide/AccessingFilesandDirectories/AccessingFilesandDirectories.html
If you want to categorically check whether an element is a file or a subdirectory:
let enumerator = FileManager.default.enumerator(atPath: contentsPath);
while let element = enumerator?.nextObject() as? String {
if(enumerator?.fileAttributes?[FileAttributeKey.type] as! FileAttributeType == FileAttributeType.typeRegular){
//this is a file
}
else if(enumerator?.fileAttributes?[FileAttributeKey.type] as! FileAttributeType == FileAttributeType.typeDirectory){
//this is a sub-directory
}
}
Recently struggled with this when handling an array of urls, whether they be a directory or not (eg. drag and drop). Ended up with this extension in swift 4, may be of use
extension Sequence where Iterator.Element == URL {
var handleDir: [URL] {
var files: [URL] = []
self.forEach { u in
guard u.hasDirectoryPath else { return files.append(u.resolvingSymlinksInPath()) }
guard let dir = FileManager.default.enumerator(at: u.resolvingSymlinksInPath(), includingPropertiesForKeys: nil) else { return }
for case let url as URL in dir {
files.append(url.resolvingSymlinksInPath())
}
}
return files
}
}
Avoid reference URLs, while they do have some advantages as stated above, they eat system resources and if you’re enumerating a large filesystem (not that large actually) your app will hit a system wall quickly and get shutdown by macOS.
Related
I want to check the pdf file with a perticular user name is available in my document directory or not. By using following code i am able to do this. But when there is no data is avalable in the document directory i want to show user a message. But i am unable to show user any message. How do do this? can anyone help me?
private func checkPatientPdfIsPresentOrNot(selectedPatient: String, completion: (_ present: Bool) -> Void){
if let documentsPathString = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true).first {
let filemanager = FileManager.default
if let files = filemanager.enumerator(atPath: documentsPathString){
while let file = files.nextObject() {
let nameWithDate = (file as! String).components(separatedBy: ".")
let fileName = nameWithDate[0]
let namewithoutDate = fileName.components(separatedBy: "_")
let name = namewithoutDate[0]
if name == selectedPatient.capitalized{
completion(true)
}
else{
completion(false)
}
}
}
else{
completion(false)
}
}
}
First of all there are – in terms of Swift – a lot of outdated APIs in your code.
Second of all as the entire code is synchronous the completion handler is pointless.
The major issue is that the completion handler is called multiple times. You should call it once passing true if the partial file name matches selectedPatient or passing false after the loop.
This is a suggestion with more contemporary code and a boolean return value.
Show the message to the user if method returns false
private func checkPatientPdfIsPresentOrNot(selectedPatient: String) -> Bool {
let fileManager = FileManager.default
do {
let documentsURL = try fileManager.url(for: .documentDirectory, in: .userDomainMask, appropriateFor: nil, create: false)
let fileURLs = try fileManager.contentsOfDirectory(at: documentsURL, includingPropertiesForKeys: [.nameKey], options: .skipsHiddenFiles)
return fileURLs.first(where: { url -> Bool in
let fileName = url.deletingPathExtension().lastPathComponent
return fileName.components(separatedBy: "_").first == selectedPatient.capitalized
}) != nil
} catch { print(error); return false }
}
I'm learning swift and wondering what's the best way to list all files with absolute path in a directory including ones from subfolders(files only)
I tried with following, but it seems listing all contents names even folder names without full paths.
let paths = FileManager.default.subpaths(atPath: folderPath)
for p in paths! {
print p
}
}
as well as
let items = try fm.contentsOfDirectory(atPath: folderPath)
googling didn't come out with any working methods.
this is for macOS 10.14
any help is appreciated!
thanks
FileManager has also a method for a deep search: enumerator(at:includingPropertiesForKeys:options:errorHandler:)
To get only the files you have to iterate the enumerator and filter the files
let url = URL(fileURLWithPath: "/path/to/directory")
var files = [URL]()
if let enumerator = FileManager.default.enumerator(at: url, includingPropertiesForKeys: [.isRegularFileKey], options: [.skipsHiddenFiles, .skipsPackageDescendants]) {
for case let fileURL as URL in enumerator {
do {
let fileAttributes = try fileURL.resourceValues(forKeys:[.isRegularFileKey])
if fileAttributes.isRegularFile! {
files.append(fileURL)
}
} catch { print(error, fileURL) }
}
print(files)
}
It's highly recommended to use URLs rather than string paths.
FileManager is right object
If you are using swift 5 or above could take advantage of AsyncStream. Below a simple Playground
import Foundation
import Combine
// Recursive iteration
func walkDirectory(at url: URL, options: FileManager.DirectoryEnumerationOptions ) -> AsyncStream<URL> {
AsyncStream { continuation in
Task {
let enumerator = FileManager.default.enumerator(at: url, includingPropertiesForKeys: nil, options: options)
while let fileURL = enumerator?.nextObject() as? URL {
if fileURL.hasDirectoryPath {
for await item in walkDirectory(at: fileURL, options: options) {
continuation.yield(item)
}
} else {
continuation.yield( fileURL )
}
}
continuation.finish()
}
}
}
// use it
let path = URL( string: "<your path>" )
let options: FileManager.DirectoryEnumerationOptions = [.skipsHiddenFiles, .skipsPackageDescendants]
Task {
let swiftFiles = walkDirectory(at: path!, options: options).filter {
$0.pathExtension == "swift"
}
for await item in swiftFiles {
print(item.lastPathComponent)
}
}
I'm using the following code to enumerate a user selected path and populate an array with files names with specific extensions.
let enumerator:FileManager.DirectoryEnumerator = fileManager.enumerator(atPath: path)!
while let element = enumerator.nextObject() as? String {
if ((element.hasSuffix("jpg"))||element.hasSuffix("playground")) {
if(!self.yourArray.contains(element))
{
self.yourArray.append(element)
}
}
I need to get the complete file path to add the file to a processing queue.
Also how I can prevent the enumerator from exploring sub directories.
Please advice.
First of all use the URL related API, it's more versatile.
Unlike the DirectoryEnumerator contentsOfDirectory returns the URLs of all items in the directory without the subdirectories.
An easy solution is an array of path extensions and the filter function
let url = URL(fileURLWithPath: "/Users/myUser/Pictures/")
let filterExtensions = ["jpg", "playground"]
do {
self.yourArray = try FileManager.default.contentsOfDirectory(at: url, includingPropertiesForKeys: nil)
.filter{ filterExtensions.contains($0.pathExtension) }
print(yourArray)
} catch {
print(error)
}
Be aware that yourArray will contain URLs, not string paths.
To use a directory enumerator:
This will allow you to get all the files in all subdirectories, not just the one level deep. Turn the path that you provided to fileManager.enumerator(atPath: path)! into a URL like below and then append the path provided by directory enumerator to this URL:
let directoryUrl = URL(fileURLWithPath: path)
let pathUrl = directoryUrl.appendingPathComponent(element)
If I was writing your code, I would also do some renames/ improvements:
func main() {
// Set up your variables
let fileManager = FileManager.default
let path = "/Users/username"
var files = [URL]() // Using a URL instead of a path.
let enumerator: FileManager.DirectoryEnumerator = fileManager.enumerator(atPath: path)!
let directoryUrl = URL(fileURLWithPath: path)
while let filepath = enumerator.nextObject() as? String {
if ((filepath.hasSuffix(".jpg")) || filepath.hasSuffix(".playground")) {
let pathUrl = directoryUrl.appendingPathComponent(filepath)
files.append(pathUrl)
}
}
}
a. How should I get all the txt files in directory?
i got a path of directory and now i should find all the txt files and change every one a little.
i try to run over all the files:
let fileManager = NSFileManager.defaultManager()
let enumerator:NSDirectoryEnumerator = fileManager.enumeratorAtPath(folderPath)
while let element = enumerator?.nextObject() as? String {
}
}
but I stuck there. How can I check if the filetype is text?
b. When i get to a directory (in the directory I run), I want get in and search there too, and in the end get out to the place I was and continue.
a is much more important to me but if I get an answer to b too it will be nice.
a. Easy and simple solution for Swift 3:
let enumerator = FileManager.default.enumerator(atPath: folderPath)
let filePaths = enumerator?.allObjects as! [String]
let txtFilePaths = filePaths.filter{$0.contains(".txt")}
for txtFilePath in txtFilePaths{
//Here you get each text file path present in folder
//Perform any operation you want by using its path
}
Your task a is completed by above code.
When talking about b, well you don't have to code for it because we are here using a enumerator which gives you the files which are inside of any directory from your given root directory.
So the enumerator does the work for you of getting inside a directory and getting you their paths.
You can use for .. in syntax of swift to enumerate through NSEnumerator.
Here is a simple function I wrote to extract all file of some extension inside a folder.
func extractAllFile(atPath path: String, withExtension fileExtension:String) -> [String] {
let pathURL = NSURL(fileURLWithPath: path, isDirectory: true)
var allFiles: [String] = []
let fileManager = NSFileManager.defaultManager()
if let enumerator = fileManager.enumeratorAtPath(path) {
for file in enumerator {
if let path = NSURL(fileURLWithPath: file as! String, relativeToURL: pathURL).path
where path.hasSuffix(".\(fileExtension)"){
allFiles.append(path)
}
}
}
return allFiles
}
let folderPath = NSBundle.mainBundle().pathForResource("Files", ofType: nil)
let allTextFiles = extractAllFile(atPath: folder!, withExtension: "txt") // returns file path of all the text files inside the folder
I needed to combine multiple answers in order to fetch the images from a directory and I'm posting my solution in Swift 3
func searchImages(pathURL: URL) -> [String] {
var imageURLs = [String]()
let fileManager = FileManager.default
let keys = [URLResourceKey.isDirectoryKey, URLResourceKey.localizedNameKey]
let options: FileManager.DirectoryEnumerationOptions = [.skipsPackageDescendants, .skipsSubdirectoryDescendants, .skipsHiddenFiles]
let enumerator = fileManager.enumerator(
at: pathURL,
includingPropertiesForKeys: keys,
options: options,
errorHandler: {(url, error) -> Bool in
return true
})
if enumerator != nil {
while let file = enumerator!.nextObject() {
let path = URL(fileURLWithPath: (file as! URL).absoluteString, relativeTo: pathURL).path
if path.hasSuffix(".png"){
imageURLs.append(path)
}
}
}
return imageURLs
}
and here is a sample call
let documentsDirectory = FileManager.default.urls(for:.documentDirectory, in: .userDomainMask)[0]
let destinationPath = documentsDirectory.appendingPathComponent("\(filename)/")
searchImages(pathURL: projectPath)
Swift 4
let documentsPath = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)[0]
let url = URL(fileURLWithPath: documentsPath)
let fileManager = FileManager.default
let enumerator: FileManager.DirectoryEnumerator = fileManager.enumerator(atPath: url.path)!
while let element = enumerator.nextObject() as? String, element.hasSuffix(".txt") {
// do something
}
let fileManager = NSFileManager.defaultManager()
let enumerator:NSDirectoryEnumerator = fileManager.enumeratorAtPath(folderPath)
while let element = enumerator?.nextObject() as? String where element.pathExtension == "txt" {
// element is txt file
}
let fileManager = NSFileManager.defaultManager()
let enumerator:NSDirectoryEnumerator = fileManager.enumeratorAtPath(folderPath!)!
while let element = enumerator.nextObject() as? String {
if (element.hasSuffix(".txt")) { // element is a txt file }
}
I'm quite new to programming a Swift and I'm trying to iterate through the files in a folder.
I took a look at the answer here and tried to translate it to Swift syntax, but didn't succeed.
let fileManager = NSFileManager.defaultManager()
let enumerator:NSDirectoryEnumerator = fileManager.enumeratorAtPath(folderPath)
for element in enumerator {
//do something
}
the error I get is:
Type 'NSDirectoryEnumerator' does not conform to protocol 'SequenceType'
My aim is to look at all the subfolders and files contained into the main folder and find all the files with a certain extension to then do something with them.
Use the nextObject() method of enumerator:
while let element = enumerator?.nextObject() as? String {
if element.hasSuffix("ext") { // checks the extension
}
}
Nowadays (early 2017) it's highly recommended to use the – more versatile – URL related API
let fileManager = FileManager.default
do {
let resourceKeys : [URLResourceKey] = [.creationDateKey, .isDirectoryKey]
let documentsURL = try fileManager.url(for: .documentDirectory, in: .userDomainMask, appropriateFor: nil, create: false)
let enumerator = FileManager.default.enumerator(at: documentsURL,
includingPropertiesForKeys: resourceKeys,
options: [.skipsHiddenFiles], errorHandler: { (url, error) -> Bool in
print("directoryEnumerator error at \(url): ", error)
return true
})!
for case let fileURL as URL in enumerator {
let resourceValues = try fileURL.resourceValues(forKeys: Set(resourceKeys))
print(fileURL.path, resourceValues.creationDate!, resourceValues.isDirectory!)
}
} catch {
print(error)
}
I couldn't get pNre's solution to work at all; the while loop just never received anything. However, I did come across this solution which works for me (in Xcode 6 beta 6, so perhaps things have changed since pNre posted the above answer?):
for url in enumerator!.allObjects {
print("\((url as! NSURL).path!)")
}
my two cents from previously anwers.. more swifty and with optionals:
let enumerator = FileManager.default.enumerator(atPath: folderPath)
while let element = enumerator?.nextObject() as? String {
print(element)
if let fType = enumerator?.fileAttributes?[FileAttributeKey.type] as? FileAttributeType{
switch fType{
case .typeRegular:
print("a file")
case .typeDirectory:
print("a dir")
}
}
}
returns all files in a directory + in subdirectories
import Foundation
let path = "<some path>"
let enumerator = FileManager.default.enumerator(atPath: path)
while let filename = enumerator?.nextObject() as? String {
print(filename)
}
Swift3 + absolute urls
extension FileManager {
func listFiles(path: String) -> [URL] {
let baseurl: URL = URL(fileURLWithPath: path)
var urls = [URL]()
enumerator(atPath: path)?.forEach({ (e) in
guard let s = e as? String else { return }
let relativeURL = URL(fileURLWithPath: s, relativeTo: baseurl)
let url = relativeURL.absoluteURL
urls.append(url)
})
return urls
}
}
Based on code from #user3441734
Swift 3
let fd = FileManager.default
fd.enumerator(atPath: "/Library/FileSystems")?.forEach({ (e) in
if let e = e as? String, let url = URL(string: e) {
print(url.pathExtension)
}
})
In case that you are getting the
'NSDirectoryEnumerator?' does not have a member named 'nextObject' error
the while loop should be:
while let element = enumerator?.nextObject() as? String {
// do things with element
}
It has something to do with optional chaining
SWIFT 3.0
Returns all files with extension in the Directory passed & its subdirectories
func extractAllFile(atPath path: String, withExtension fileExtension:String) -> [String] {
let pathURL = NSURL(fileURLWithPath: path, isDirectory: true)
var allFiles: [String] = []
let fileManager = FileManager.default
let pathString = path.replacingOccurrences(of: "file:", with: "")
if let enumerator = fileManager.enumerator(atPath: pathString) {
for file in enumerator {
if #available(iOS 9.0, *) {
if let path = NSURL(fileURLWithPath: file as! String, relativeTo: pathURL as URL).path, path.hasSuffix(".\(fileExtension)"){
let fileNameArray = (path as NSString).lastPathComponent.components(separatedBy: ".")
allFiles.append(fileNameArray.first!)
}
} else {
// Fallback on earlier versions
print("Not available, #available iOS 9.0 & above")
}
}
}
return allFiles
}
Updating for Swift 3:
let fileManager = FileManager() // let fileManager = NSFileManager.defaultManager()
let en=fileManager.enumerator(atPath: the_path) // let enumerator:NSDirectoryEnumerator = fileManager.enumeratorAtPath(folderPath)
while let element = en?.nextObject() as? String {
if element.hasSuffix("ext") {
// do something with the_path/*.ext ....
}
}
Adding to vadian's response -- the Apple docs mention that Path-based URLs are simpler in some ways, however file reference URLs have the advantage that the reference remains valid if the file is moved or renamed while your app is running.
From the documentation for "Accessing Files and Directories":
"Path-based URLs are easier to manipulate, easier to debug, and are generally preferred by classes such as NSFileManager. An advantage of file reference URLs is that they are less fragile than path-based URLs while your app is running. If the user moves a file in the Finder, any path-based URLs that refer to the file immediately become invalid and must be updated to the new path. However, as long as the file moved to another location on the same disk, its unique ID does not change and any file reference URLs remain valid."
https://developer.apple.com/library/content/documentation/FileManagement/Conceptual/FileSystemProgrammingGuide/AccessingFilesandDirectories/AccessingFilesandDirectories.html
If you want to categorically check whether an element is a file or a subdirectory:
let enumerator = FileManager.default.enumerator(atPath: contentsPath);
while let element = enumerator?.nextObject() as? String {
if(enumerator?.fileAttributes?[FileAttributeKey.type] as! FileAttributeType == FileAttributeType.typeRegular){
//this is a file
}
else if(enumerator?.fileAttributes?[FileAttributeKey.type] as! FileAttributeType == FileAttributeType.typeDirectory){
//this is a sub-directory
}
}
Recently struggled with this when handling an array of urls, whether they be a directory or not (eg. drag and drop). Ended up with this extension in swift 4, may be of use
extension Sequence where Iterator.Element == URL {
var handleDir: [URL] {
var files: [URL] = []
self.forEach { u in
guard u.hasDirectoryPath else { return files.append(u.resolvingSymlinksInPath()) }
guard let dir = FileManager.default.enumerator(at: u.resolvingSymlinksInPath(), includingPropertiesForKeys: nil) else { return }
for case let url as URL in dir {
files.append(url.resolvingSymlinksInPath())
}
}
return files
}
}
Avoid reference URLs, while they do have some advantages as stated above, they eat system resources and if you’re enumerating a large filesystem (not that large actually) your app will hit a system wall quickly and get shutdown by macOS.