How to access file included in app bundle in Swift?

Simply by searching in the app bundle for the resource

var filePath = NSBundle.mainBundle().URLForResource("file", withExtension: "txt")

However you can't write to it because it is in the app resources directory and you have to create it in the document directory to write to it

var documentsDirectory: NSURL?var fileURL: NSURL?documentsDirectory = NSFileManager.defaultManager().URLsForDirectory(.DocumentDirectory, inDomains: .UserDomainMask).last!fileURL = documentsDirectory!.URLByAppendingPathComponent("file.txt")if (fileURL!.checkResourceIsReachableAndReturnError(nil)) {    print("file exist")}else{    print("file doesnt exist")    NSData().writeToURL(fileURL!,atomically:true)}

now you can access it from fileURL

EDIT - 28 August 2018

This is how to do it in Swift 4.2

var filePath = Bundle.main.url(forResource: "file", withExtension: "txt")

To create it in the document directory

if let documentsDirectory = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).last {   let fileURL = documentsDirectory.appendingPathComponent("file.txt")   do {       if try fileURL.checkResourceIsReachable() {           print("file exist")       } else {           print("file doesnt exist")           do {            try Data().write(to: fileURL)           } catch {               print("an error happened while creating the file")           }       }   } catch {       print("an error happened while checking for the file")   }}

Swift 3, based on Karim’s answer.

Reading

You can read files included in an app’s bundle through the bundle’s resource:

let fileURL = Bundle.main.url(forResource:"filename", withExtension: "txt")

Writing

However, you can’t write there. You will need to create a copy, preferably in the Documents directory:

func makeWritableCopy(named destFileName: String, ofResourceFile originalFileName: String) throws -> URL {    // Get Documents directory in app bundle    guard let documentsDirectory = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).last else {        fatalError("No document directory found in application bundle.")    }    // Get URL for dest file (in Documents directory)    let writableFileURL = documentsDirectory.appendingPathComponent(destFileName)    // If dest file doesn’t exist yet    if (try? writableFileURL.checkResourceIsReachable()) == nil {        // Get original (unwritable) file’s URL        guard let originalFileURL = Bundle.main.url(forResource: originalFileName, withExtension: nil) else {            fatalError("Cannot find original file “\(originalFileName)” in application bundle’s resources.")        }        // Get original file’s contents        let originalContents = try Data(contentsOf: originalFileURL)        // Write original file’s contents to dest file        try originalContents.write(to: writableFileURL, options: .atomic)        print("Made a writable copy of file “\(originalFileName)” in “\(documentsDirectory)\\\(destFileName)”.")    } else { // Dest file already exists        // Print dest file contents        let contents = try String(contentsOf: writableFileURL, encoding: String.Encoding.utf8)        print("File “\(destFileName)” already exists in “\(documentsDirectory)”.\nContents:\n\(contents)")    }    // Return dest file URL    return writableFileURL}

Example usage:

let stuffFileURL = try makeWritableCopy(named: "Stuff.txt", ofResourceFile: "Stuff.txt")try "New contents".write(to: stuffFileURL, atomically: true, encoding: String.Encoding.utf8)

Just a quick update for using this code with Swift 4:

Bundle.main.url(forResource:"YourFile", withExtension: "FileExtension")

And the following has been updated to account for writing the file out:

var myData: Data!func checkFile() {    if let documentsDirectory = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).last {        let fileURL = documentsDirectory.appendingPathComponent("YourFile.extension")        do {            let fileExists = try fileURL.checkResourceIsReachable()            if fileExists {                print("File exists")            } else {                print("File does not exist, create it")                writeFile(fileURL: fileURL)            }        } catch {            print(error.localizedDescription)        }    }}func writeFile(fileURL: URL) {    do {        try myData.write(to: fileURL)    } catch {        print(error.localizedDescription)    }}

This particular example is not the most flexible, but with a little bit of work you can easily pass in your own file names, extensions and data values.