ios - ¿Guardar cadena en el NSUserDefaults?

cocoa-touch

Question

¿Cómo guardar una cadena en el NSUserDefaults ?

Answer 1

Algo como esto:

NSUserDefaults *prefs = [NSUserDefaults standardUserDefaults];
// saving an NSString
[prefs setObject:@"TextToSave" forKey:@"keyToLookupString"];

Luego para recuperar:

NSUserDefaults *prefs = [NSUserDefaults standardUserDefaults];
// getting an NSString
NSString *myString = [prefs stringForKey:@"keyToLookupString"];

Realmente deberías revisar la Referencia de clase NSUserDefaults de Apple y quizás también este tutorial: Tutorial de programación de iPhone - Guardar / recuperar datos usando NSUserDefaults

Answer 2

Aquí es cómo hacer lo mismo con Swift;

var valueToSave = "someValue"
NSUserDefaults.standardUserDefaults().setObject(valueToSave, forKey: "preferenceName")

Para recuperarlo más tarde;

if let savedValue = NSUserDefaults.standardUserDefaults().stringForKey("preferenceName") {
// Do something with savedValue
}

En Swift 3.0

var valueToSave = "someValue"
UserDefaults.standard.set(valueToSave, forKey: "preferenceName")
if let savedValue = UserDefaults.standard.string(forKey: "preferenceName") {
}

Answer 3

Aquí para Swift, creo dos funciones que requieren guardar y recuperar valor para la clave de Preference

Puede ser que esto sea una ayuda completa para ti.

// para guardar el objeto

static func setObject(value:AnyObject ,key:String)
{
let pref = NSUserDefaults.standardUserDefaults()
pref.setObject(value, forKey: key)
pref.synchronize()
}
static func getObject(key:String) -> AnyObject
{
let pref = NSUserDefaults.standardUserDefaults()
return pref.objectForKey(key)!
}

Answer 4

En Swift4.2 y Xcode 10

//Save
UserDefaults.standard.set(true, forKey: "Key1") //Bool
UserDefaults.standard.set(1, forKey: "Key2") //Integer
UserDefaults.standard.set("This is my string", forKey: "Key3") //String
UserDefaults.standard.synchronize()
//Retrive
UserDefaults.standard.bool(forKey: "Key1")
UserDefaults.standard.integer(forKey: "Key2")
UserDefaults.standard.string(forKey: "Key3")
//Remove
UserDefaults.standard.removeObject(forKey: "Key3")

Answer 5

No olvide esta afirmación porque de lo contrario no siempre funcionará:

[standardUserDefaults synchronize];

Answer 6

Una buena práctica es también usar una constante para la clave para evitar errores donde no almacena y lee con la misma clave

NSString* const TIME_STAMPS_KEY = @"TIME_STAMPS_KEY";

Answer 7

actualización para Swift 3

func setObject(value:AnyObject ,key:String)
{
let pref = UserDefaults.standard
pref.set(value, forKey: key)
pref.synchronize()
}
func getObject(key:String) -> AnyObject
{
let pref = UserDefaults.standard
return pref.object(forKey: key)! as AnyObject
}

Answer 8

más precisamente

-(void)saveToUserDefaults:(NSString*)myString
{
NSUserDefaults *standardUserDefaults = [NSUserDefaults standardUserDefaults];
if (standardUserDefaults) {
[standardUserDefaults setObject:myString forKey:@"timestamps"];
[standardUserDefaults synchronize];
}
}

Answer 9

[[NSUserDefaults standardUserDefaults] setValue:aString forKey:aKey]

Answer 10

En Swift 4.0.3 Xcode 9

============set Data in UserDefaults =========
UserDefaults.standard.set(userName, forKey: "userName")
UserDefaults.standard.synchronize()
============Get Data in UserDefaults =========
let userName = UserDefaults.standard.string(forKey: "userName")
print(userName ?? "Gera")
userNameTextField.text = ""+userName!

Answer 11

Para ahorrar usa esto:

[[NSUserDefaults standardUserDefaults]setObject:@"YES" forKey:@"KTerminated"];
[[NSUserDefaults standardUserDefaults]synchronize];

Para el uso de Retriveing ​​esto:

[[[NSUserDefaults standardUserDefaults]stringForKey:@"KTerminated"] isEqualToString:@"YES"];

Answer 12

Primera vista

 {
NSMutableArray *array; }
- (void)viewDidLoad {
[super viewDidLoad];
array = [[NSMutableArray alloc]init];
array = [[NSUserDefaults standardUserDefaults]objectForKey:@"userlist"];
NSLog(@"%lu",(unsigned long)array.count);
if (array>0)
{
for (int i=0; i<array.count; i++)
{
NSDictionary *dict1 = @{@"Username":[[array valueForKey:@"Username"] objectAtIndex:i],@"Mobilenumber":[[array valueForKey:@"Mobilenumber"] objectAtIndex:i],@"Firstname":[[array valueForKey:@"Firstname"] objectAtIndex:i],@"Lastname":[[array valueForKey:@"Lastname"] objectAtIndex:i],@"dob":[[array valueForKey:@"dob"] objectAtIndex:i],@"image":[[array valueForKey:@"image"] objectAtIndex:i]};
NSLog(@"%@",dict1);
NSArray *array1 = [[NSArray alloc]initWithObjects:dict1, nil];
[[NSUserDefaults standardUserDefaults] setObject:array1 forKey:@"UserList"];
}
}
}

Selector de imágenes

 - (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info {
UIImage *chosenImage = info[UIImagePickerControllerEditedImage];
self.imaGe.image = chosenImage;
[picker dismissViewControllerAnimated:YES completion:NULL];
}

• (IBAction) submitBton: (id) remitente {

  NSMutableArray *array2 = [[NSMutableArray alloc]initWithArray:
  [[NSUserDefaults standardUserDefaults]objectForKey:
  @"userlist"]];
  UIImage *ima = _imaGe.image;
  NSData *imagedata = UIImageJPEGRepresentation(ima,100);
  NSDictionary *dict = @{@"Username":_userTxt.text,@"Lastname":_lastTxt.text,@"Firstname":_firstTxt.text,@"Mobilenumber":_mobTxt.text,@"dob":_dobTxt.text,@"image":imagedata};
  [array2 addObject:dict];
  [[NSUserDefaults standardUserDefaults]setObject:array2
  forKey:@"userlist"];
  NSLog(@"%@",array2);
  [self performSegueWithIdentifier:@"second" sender:self];
  }

  • (IBAction) selectImg: (id) remitente {

    UIImagePickerController * picker = [[UIImagePickerController
    alloc] init]; picker.delegate = self; picker.allowsEditing = YES; picker.sourceType =
    UIImagePickerControllerSourceTypePhotoLibrary; [self presentViewController: selector animado: SÍ finalización: NULL];

    }

segunda vista {NSMutableArray * arr; }

- (void)viewDidLoad {
[super viewDidLoad];
arr =[[NSMutableArray alloc]init];
arr = [[NSUserDefaults standardUserDefaults]objectForKey:@"userlist"]; }
#pragma mark- TableView DataSource
-(NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
return 1; }
-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
return arr.count; }
-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *cellId = @"tablecell";
TableViewCell *cell =[tableView dequeueReusableCellWithIdentifier:cellId];
cell.userLbl.text =[[arr valueForKey:@"username"] objectAtIndex:indexPath.row];
cell.ageLbl.text =[[arr valueForKey:@"dob"] objectAtIndex:indexPath.row];
cell.profileImg.image =[UIImage imageNamed:[[arr valueForKey:@"image"] objectAtIndex:indexPath.row]];
return cell; }

Answer 13

-(void)saveToUserDefaults:(NSString*)string_to_store keys:(NSString *)key_for_the_String
{
NSUserDefaults *standardUserDefaults = [NSUserDefaults standardUserDefaults];
if (standardUserDefaults) {
[standardUserDefaults setObject:string_to_store forKey:key_for_the_String];
[standardUserDefaults synchronize];
}
}

Y llámalo por:

[self saveToUserDefaults:@"string_to_store" : @"key_for_the_string"];

Recupera la cadena usando:

NSString * stored_string = [[NSUserDefaults standardUserDefaults] stringforkey:key_for_the_String]

Answer 14

NSString *valueToSave = @"someValue";
[[NSUserDefaults standardUserDefaults] setObject:valueToSave forKey:@"preferenceName"];
[[NSUserDefaults standardUserDefaults] synchronize];

para recuperarlo mas tarde

NSString *savedValue = [[NSUserDefaults standardUserDefaults]
stringForKey:@"preferenceName"];

Answer 15

NSUserDefaults *prefs = [NSUserDefaults standardUserDefaults];
// saving an NSString
[prefs setObject:@"TextToSave" forKey:@"keyToLookupString"];
// saving an NSInteger
[prefs setInteger:42 forKey:@"integerKey"];
// saving a Double
[prefs setDouble:3.1415 forKey:@"doubleKey"];
// saving a Float
[prefs setFloat:1.2345678 forKey:@"floatKey"];
// This is suggested to synch prefs, but is not needed (I didn''t put it in my tut)
[prefs synchronize];

Recuperando

NSUserDefaults *prefs = [NSUserDefaults standardUserDefaults];
// getting an NSString
NSString *myString = [prefs stringForKey:@"keyToLookupString"];
// getting an NSInteger
NSInteger myInt = [prefs integerForKey:@"integerKey"];
// getting an Float
float myFloat = [prefs floatForKey:@"floatKey"];