If you have a look at the NSUserDefaults documentation you will see a method – (NSDictionary *) dictionaryRepresentation. Using this method on the standard user defaults, you can get a list of all keys in the user defaults. You can then use this to clear the user defaults: – (void)resetDefaults { NSUserDefaults * defs = … Read more
In Swift 4 this is pretty much trivial. Make your struct codable simply by marking it as adopting the Codable protocol: struct Song:Codable { var title: String var artist: String } Now let’s start with some data: var songs: [Song] = [ Song(title: “Title 1”, artist: “Artist 1”), Song(title: “Title 2”, artist: “Artist 2”), Song(title: … Read more
Objective C all values: NSLog(@”%@”, [[[NSUserDefaults standardUserDefaults] dictionaryRepresentation] allValues]); all keys: NSLog(@”%@”, [[[NSUserDefaults standardUserDefaults] dictionaryRepresentation] allKeys]); all keys and values: NSLog(@”%@”, [[NSUserDefaults standardUserDefaults] dictionaryRepresentation]); using for: NSArray *keys = [[[NSUserDefaults standardUserDefaults] dictionaryRepresentation] allKeys]; for(NSString* key in keys){ // your code here NSLog(@”value: %@ forKey: %@”,[[NSUserDefaults standardUserDefaults] valueForKey:key],key); } Swift all values: print(UserDefaults.standard.dictionaryRepresentation().values) all keys: print(UserDefaults.standard.dictionaryRepresentation().keys) … Read more
In Swift 4 or higher, Use Codable. In your case, use following code. class Blog: Codable { var blogName: String? } Now create its object. For example: var blog = Blog() blog.blogName = “My Blog” Now encode it like this: if let encoded = try? JSONEncoder().encode(blog) { UserDefaults.standard.set(encoded, forKey: “blog”) } and decode it like … Read more
You need to create Data instance from your JobCategory model using JSONEncoder and store that Data instance in UserDefaults and later decode using JSONDecoder. struct JobCategory: Codable { let id: Int let name: String } // To store in UserDefaults if let encoded = try? JSONEncoder().encode(category) { UserDefaults.standard.set(encoded, forKey: UserDefaultsKeys.jobCategory.rawValue) } // Retrieve from UserDefaults … Read more
You can set your boolean by using: [[NSUserDefaults standardUserDefaults] setBool:YES forKey:@”logged_in”]; [[NSUserDefaults standardUserDefaults] synchronize]; and read it by using this code: if(![[NSUserDefaults standardUserDefaults] boolForKey:@”logged_in”]) { [self displayLogin]; } else { [self displayMainScreen]; }
The question reads “array of array” but I think most people probably come here just wanting to know how to save an array to UserDefaults. For those people I will add a few common examples. String array Save array let array = [“horse”, “cow”, “camel”, “sheep”, “goat”] let defaults = UserDefaults.standard defaults.set(array, forKey: “SavedStringArray”) Retrieve … Read more
Astun has a great answer. See below for the Swift 3 version. func isKeyPresentInUserDefaults(key: String) -> Bool { return UserDefaults.standard.object(forKey: key) != nil }
I think this is due to a bug in the iOS8 Beta Simulator. The expected behavior is that when the app is deleted, the NSUserDefaults for that app are deleted as well. However, NSUserDefaults are NOT deleted when you remove an app from the simulator. They are correctly deleted when you delete them from a … Read more
They are usually not reset unless the user deletes the app. For basic data, NSUserDefaults is the best way to save data such as preferences, dates, strings etc. If you are looking to save images and files, the file system is a better bet.