将字符串保存到NSUserDefaults？

Question

如何将字符串保存到NSUserDefaults？

Answer 1

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

把它找回来以后

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

Answer 2

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

Answer 3

更精确地

-(void)saveToUserDefaults:(NSString*)myString 
{ 
    NSUserDefaults *standardUserDefaults = [NSUserDefaults standardUserDefaults]; 

    if (standardUserDefaults) { 
     [standardUserDefaults setObject:myString forKey:@"timestamps"]; 
     [standardUserDefaults synchronize]; 
    } 
} 

Answer 4

事情是这样的：

NSUserDefaults *prefs = [NSUserDefaults standardUserDefaults]; 

// saving an NSString 
[prefs setObject:@"TextToSave" forKey:@"keyToLookupString"]; 

然后检索：

NSUserDefaults *prefs = [NSUserDefaults standardUserDefaults]; 

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

你真的应该看看苹果的NSUserDefaults的类参考，也可能这个教程：iPhone Programming Tutorial – Saving/Retrieving Data Using NSUserDefaults

Answer 5

不要忘了这个说法，因为否则可能并不总是工作：

[standardUserDefaults synchronize]; 

Answer 6

一个不错的做法是使用一个常量作为密钥，以避免在没有使用相同密钥存储和读取的情况下发生错误

NSString* const TIME_STAMPS_KEY = @"TIME_STAMPS_KEY"; 

Answer 7

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]; 

检索

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"]; 

Answer 8

这里是如何做相同的雨燕;

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

以后拿回来;

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

在夫特3。0

var valueToSave = "someValue" 
UserDefaults.standard.set(valueToSave, forKey: "preferenceName") 

if let savedValue = UserDefaults.standard.string(forKey: "preferenceName") { 

} 

Answer 9

​​

并通过调用它：

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

通过检索字符串：

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

Answer 10

为了节约使用本：

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

对于Retriveing使用：

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

Answer 11

这里对于斯威夫特我创建两个功能，要求保存和优先重点retrive值

可能这是帮助全为ü

//用于保存对象

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 12

的firstView

{ 
    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"]; 
     } 

    } 
    } 

ImagePicker

 - (void)imagePickerController:(UIImagePickerController *)picker   didFinishPickingMediaWithInfo:(NSDictionary *)info { 

    UIImage *chosenImage = info[UIImagePickerControllerEditedImage]; 
    self.imaGe.image = chosenImage; 

    [picker dismissViewControllerAnimated:YES completion:NULL]; 
    } 

• （IBAction为）submitBton：（ID）发送方{

  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为）chooseImg：（ID）发送方{

    的UIImagePickerController *挑选器= [[的UIImagePickerController
    的alloc] INIT]; picker.delegate = self; picker.allowsEditing = YES; picker.sourceType =
    UIImagePickerControllerSourceTypePhotoLibrary; [自presentViewController：拾取器动画：是完成：NULL];

    }

---

第二查看 { 的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

更新夫特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 14

在夫特4.0。3 Xcode中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!