How to auto clear NSUserDefault values in swift?

5 Solutions Collect From Internet About “How to auto clear NSUserDefault values in swift?”

check how many keys are already stored

print(NSUserDefaults.standardUserDefaults().dictionaryRepresentation().keys.array.count)

add just another key

NSUserDefaults.standardUserDefaults().setBool(true, forKey: "justAnotherKey1")
NSUserDefaults.standardUserDefaults().setBool(true, forKey: "justAnotherKey2")

check how many keys are already stored again (+2)

print(NSUserDefaults.standardUserDefaults().dictionaryRepresentation().keys.array.count)

now create a loop to remove your object for the keys

for key in NSUserDefaults.standardUserDefaults().dictionaryRepresentation().keys {
    NSUserDefaults.standardUserDefaults().removeObjectForKey(key.description)
}

check how many keys you have again

print(NSUserDefaults.standardUserDefaults().dictionaryRepresentation().keys.array.count)

update: Xcode 7.2.1 • Swift 2.1.1 (note NSUserDefaults doesn’t work in playground anymore, so it needs to be tested in a real project)

print(Array(NSUserDefaults.standardUserDefaults().dictionaryRepresentation().keys).count)

NSUserDefaults.standardUserDefaults().setBool(true, forKey: "justAnotherKey1")
NSUserDefaults.standardUserDefaults().setBool(true, forKey: "justAnotherKey2")

print(Array(NSUserDefaults.standardUserDefaults().dictionaryRepresentation().keys).count)

for key in Array(NSUserDefaults.standardUserDefaults().dictionaryRepresentation().keys) {
    NSUserDefaults.standardUserDefaults().removeObjectForKey(key)
}

print(Array(NSUserDefaults.standardUserDefaults().dictionaryRepresentation().keys).count)

The swift counterpart for your objective-c code is this

 let appDomain = NSBundle.mainBundle().bundleIdentifier!

 NSUserDefaults.standardUserDefaults().removePersistentDomainForName(appDomain)

Swift 3.0

let appDomain = Bundle.main.bundleIdentifier!
UserDefaults.standard.removePersistentDomain(forName: appDomain)

Swift 3.0 Solution

let appDomain = Bundle.main.bundleIdentifier!
UserDefaults.standard.removePersistentDomain(forName: appDomain) 
defaults.setObject(nil, forKey: "userEmail")

doing that, you put nil, so you clear

There is no “auto clear”. Just get all the existing NSUserDefaults keys and set them all to nil.

To get all the keys, get the NSUserDefaults dictionaryRepresentation and get its keys (allKeys in Objective-C).