Save file in document directory in swift 3?

Question

I am saving files in a document directory in swift 3 with this code:

fileManager = FileManager.default
// let documentDirectory = fileManager?.urls(for: .documentDirectory, in: .userDomainMask).first as String
var path = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)[0] as String
path = path + name

let image = #imageLiteral(resourceName: "Notifications")
let imageData = UIImageJPEGRepresentation(image, 0.5)
let bool = fileManager?.createFile(atPath: path, contents: imageData, attributes: nil)

print("bool is \(bool)")
return true

But as you can see, I am not using filemanager to get document directory path as filemanager gives only URL not string.

Questions:

How to get string from file manager?
Is there any chance of crash in my code?

`let fileManager = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first?.path` — Willjay, Jun 20 '17 at 07:26

vadian · Accepted Answer · 2020-06-01T16:00:20.543

89

Please think the other way round.

URL is the recommended way to handle file paths because it contains all convenience methods for appending and deleting path components and extensions – rather than String which Apple has removed those methods from.

You are discouraged from concatenating paths like path = path + name. It's error-prone because you are responsible for all slash path separators.

Further you don't need to create a file with FileManager. Data has a method to write data to disk.

let fileManager = FileManager.default
do {
    let documentDirectory = try fileManager.url(for: .documentDirectory, in: .userDomainMask, appropriateFor:nil, create:false)
    let fileURL = documentDirectory.appendingPathComponent(name)
    let image = #imageLiteral(resourceName: "Notifications")
    if let imageData = image.jpegData(compressionQuality: 0.5) {
        try imageData.write(to: fileURL)
        return true
    }
} catch {
    print(error)
}
return false

edited Jun 01 '20 at 16:00

answered Jun 20 '17 at 07:34

vadian

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4

A check `if fileManager.fileExists(atPath: path) { print("File already there") }` Should be there. – Jack Jun 18 '18 at 04:51
Can i save whole folder with images in document directory ? – Khushbu Desai Jun 22 '18 at 09:05
@KhushbuDesai Yes, I suppose. – vadian Jun 22 '18 at 09:07
@vadian Can you please help me with this? I will share my Code, My folder is copied in doc directory but without data. – Khushbu Desai Jun 22 '18 at 10:11
What is going on here: 'let image = #imageLiteral(resourceName: "Notifications")' What does resourceName represent? – Moondra Jul 17 '18 at 22:28
@Moondra Please read https://medium.com/ios-os-x-development/be-literal-76e9b4389eda – vadian Jul 18 '18 at 03:58
1

@jack https://forums.developer.apple.com/thread/97497 --> "it is generally regarded s incorrect" etc. What's your take on this? – Kheldar Dec 10 '19 at 20:59

score 4 · Answer 2 · answered Jan 02 '18 at 22:01

following the above example given by vadian the only line you need to save a (Data)file in Document Directory is:

try imageData.write(to: fileURL)

Getting the file path is the interesting part

ex: create the file path

 func createNewDirPath( )->URL{ 

let dirPathNoScheme = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)[0] as String

    //add directory path file Scheme;  some operations fail w/out it
    let dirPath = "file://\(dirPathNoScheme)"
    //name your file, make sure you get the ext right .mp3/.wav/.m4a/.mov/.whatever
    let fileName = "thisIsYourFileName.mov"
    let pathArray = [dirPath, fileName]
    let path = URL(string: pathArray.joined(separator: "/"))

    //use a guard since the result is an optional
    guard let filePath = path else {
        //if it fails do this stuff:
        return URL(string: "choose how to handle error here")!
    }
    //if it works return the filePath
    return filePath
}

call the function:

let shinnyNewURLpath = createNewDirPath( ) 


//write data to file using one line in do/catch operation
do {
   try yourDataObject?.write(to: shinnyNewURLpath)
    } 
catch {
       print("catch error",error.localizedDescription)
 }

score 4 · Answer 3 · edited Jul 02 '19 at 14:59

I use the following method for creating "Test.txt" file. Hope it helps you.

func createFile() {
    let fileName = "Test"
    let documentDirURL = try! FileManager.default.url(for: .documentDirectory, in: .userDomainMask, appropriateFor: nil, create: true)
    let fileURL = documentDirURL.appendingPathComponent(fileName).appendingPathExtension("txt")
    print("File PAth: \(fileURL.path)")
}

score -13 · Answer 4 · edited Nov 20 '20 at 14:16

func copyandpaste() {
   var path = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)
   let dbpath: NSString = path[0] as NSString
        
   let strdbpath =  dbpath.strings(byAppendingPaths: ["mydb.db"])[0]
   print(strdbpath)
   let fmnager  =  FileManager.default
        
   if !fmnager.fileExists(atPath: strdbpath) {
      let local  = Bundle.main.path(forResource: "mydb", ofType: "db")
      do {
         try fmnager.copyItem(atPath: local!, toPath: strdbpath)
      } catch {
      }
   }        
}

Save file in document directory in swift 3?

4 Answers4

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