How do I delete a file in my apps documents directory?

Given, a file of path [[self documentsDirectory] stringByAppendingPathComponent:@"my开发者_JAVA百科Files/aFile.txt"], How do I delete a file in my apps documents directory?

NSFileManager is a very handy tool:

[[NSFileManager defaultManager] removeItemAtPath: pathToFile error: &error];

With Swift 3, FileManager has a method called removeItem(at:). removeItem(at:) has the following declaration:

func removeItem(at URL: URL) throws

Removes the file or directory at the specified URL.

The code fragment below shows how to delete a file using removeItem(at:):

do {
    try FileManager.default.removeItem(at: fileUrl)
} catch {
    print("Could not delete file: \(error)")
}

As a complete example, the following UIViewController subclass implementation shows how to copy a file from the app bundle to a specific url in the document directory, delete a file at a specific url in document directory and check if a file exists at a specific url in document directory:

import UIKit

class ViewController: UIViewController {

    @IBAction func copyFile(_ sender: UIButton) {
        // Get app bundle file url
        guard let bundleFileUrl = 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 bundle file to document directory
        if !FileManager.default.fileExists(atPath: documentDirectoryFileUrl.path) {
            do {
                try FileManager.default.copyItem(at: bundleFileUrl, to: documentDirectoryFileUrl)
            } catch {
                print("Could not copy file: \(error)")
            }
        }
    }

    @IBAction func deleteFile(_ sender: UIButton) {
        // Get 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")

        // Delete file in document directory
        if FileManager.default.fileExists(atPath: documentDirectoryFileUrl.path) {
            do {
                try FileManager.default.removeItem(at: documentDirectoryFileUrl)
            } catch {
                print("Could not delete file: \(error)")
            }
        }
    }

    @IBAction func checkIfFileExist(_ sender: UIButton) {
        // Get destination url in document directory for file
        guard let documentsDirectory = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first else { return }
        let outputUrl = documentsDirectory.appendingPathComponent("Movie.mov")

        // Print if file exists in document directory or not
        FileManager.default.fileExists(atPath: outputUrl.path) ? print("File exists") : print("File does not exist")
    }

}

For Swift 3.x and Xcode 8.x

func removeItemForDocument(itemName:String, fileExtension: String) {
  let fileManager = FileManager.default
  let NSDocumentDirectory = FileManager.SearchPathDirectory.documentDirectory
  let NSUserDomainMask = FileManager.SearchPathDomainMask.userDomainMask
  let paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, true)
  guard let dirPath = paths.first else {
      return
  }  
  let filePath = "\(dirPath)/\(itemName).\(fileExtension)"
  do {
    try fileManager.removeItem(atPath: filePath)
  } catch let error as NSError {
    print(error.debugDescription)
  }}