Getting Optional("") When Trying to Get Value from Keychain

Getting Optional( ) when trying to get value from KeyChain

You get the Optional("") because the optional value is not unwrapped. You need to put a ! after the object and you won't get the Optional("") bit any more. I would show you the code but you haven't shown us the print() statement. I made some sample ones below that I think would replicate the problem, though I haven't tried them.

var value:String?
value = "Hello, World"

print("The Value Is \(value)") // Prints "The Value Is Optional(Hello, World)"
print("The Value Is \(value!)")// Prints "The Value Is Hello, World"

Im hoping this answers your question or at least points you in the right direction, just ask if you need more information or a better example.

Get rid of these Optional values

You're overusing !. You don't need them. Try to learn more about implicitly unwrapped optionals, optionals, ... Your code is a mess (no offense, everybody's learning).

Back to your optional problem, it's caused by this line:

let username : String! = String(NSString(data: NsDataUsername!, encoding: NSUTF8StringEncoding))

convenience init?(data: NSData, encoding: UInt) - inner part utilizes failable initializer, so, NSString? is the result. Then initialization of String with optional NSString? produces optional as well. But, it has no sense at all do it in this way.

First part - remove optional

Utilizing new guard:

guard let loadedPassword = NSString(data: passwordData, encoding: NSUTF8StringEncoding) else {
  fatalError("Ooops")
}

loadedPassword contains NSString (not NSString?) now.

Second part - NSString -> String

You did probably read (if not, read) Strings and Characters about bridging, ... If you can freely exchange NSString with String, you can think that you're done:

var dict = [String:String]()
dict["password"] = loadedPassword

Nope. It produces following error:

NSString is not implicitly convertible to String; did you mean to
use 'as' to explicitly convert?

Slight change and now you're done:

var dict = [String:String]()
dict["password"] = loadedPassword as String

Complete example

let password = "Hallo"
guard let passwordData = password.dataUsingEncoding(NSUTF8StringEncoding) else {
  fatalError("Ooops")
}

// save/load to/from keychain

guard let loadedPassword = NSString(data: passwordData, encoding: NSUTF8StringEncoding) else {
  fatalError("Ooops")
}

var dict = [String:String]()
dict["password"] = loadedPassword as String

print(dict) // "[password: Hallo]\n"

Save and retrieve value via KeyChain

Well, I just used out source etc and made my self nice helper :
Enjoy!

 class func save(key: String, data: NSData) {
        let query = [
            kSecClass as String       : kSecClassGenericPassword as String,
            kSecAttrAccount as String : key,
            kSecValueData as String   : data ]

        SecItemDelete(query as CFDictionaryRef)

        let status: OSStatus = SecItemAdd(query as CFDictionaryRef, nil)

    }

    class func load(key: String) -> NSData? {
        let query = [
            kSecClass as String       : kSecClassGenericPassword,
            kSecAttrAccount as String : key,
            kSecReturnData as String  : kCFBooleanTrue,
            kSecMatchLimit as String  : kSecMatchLimitOne ]

        var dataTypeRef :Unmanaged<AnyObject>?

        let status: OSStatus = SecItemCopyMatching(query, &dataTypeRef)

        if status == noErr {
            return (dataTypeRef!.takeRetainedValue() as! NSData)
        } else {
            return nil
        }


    }

    class func stringToNSDATA(string : String)->NSData
    {
        let _Data = (string as NSString).dataUsingEncoding(NSUTF8StringEncoding)
        return _Data!

    }


    class func NSDATAtoString(data: NSData)->String
    {
        var returned_string : String = NSString(data: data, encoding: NSUTF8StringEncoding)! as String
        return returned_string
    }

    class func intToNSDATA(r_Integer : Int)->NSData
    {

            var SavedInt: Int = r_Integer
            let _Data = NSData(bytes: &SavedInt, length: sizeof(Int))
        return _Data

    }
    class func NSDATAtoInteger(_Data : NSData) -> Int
    {
            var RecievedValue : Int = 0
            _Data.getBytes(&RecievedValue, length: sizeof(Int))
            return RecievedValue

    }
    class func CreateUniqueID() -> String
    {
        var uuid: CFUUIDRef = CFUUIDCreate(nil)
        var cfStr:CFString = CFUUIDCreateString(nil, uuid)

        var nsTypeString = cfStr as NSString
        var swiftString:String = nsTypeString as String
        return swiftString
    }

    //EXAMPLES
//    
//    //Save And Parse Int


//    var Int_Data = KeyChain.intToNSDATA(555)
//    KeyChain.save("MAMA", data: Int_Data)
//    var RecievedDataAfterSave = KeyChain.load("MAMA")
//    var NSDataTooInt = KeyChain.NSDATAtoInteger(RecievedDataAfterSave!)
//    println(NSDataTooInt)
//    
//    
//    //Save And Parse String


//    var string_Data = KeyChain.stringToNSDATA("MANIAK")
//    KeyChain.save("ZAHAL", data: string_Data)
//    var RecievedDataStringAfterSave = KeyChain.load("ZAHAL")
//    var NSDATAtoString = KeyChain.NSDATAtoString(RecievedDataStringAfterSave!)
//    println(NSDATAtoString)

Swift + Locksmith: Not getting stored Keychain Value

Looks like you're pulling your "password" string out of the dictionary incorrectly. Don't use the .stringValue function in this case. Change this line:

if let passwordSaved = dictionary!["password"]?.stringValue {

to

if let passwordSaved = dictionary!["password"] as? String {

Getting value of NSCoding into string - KeychainWrapper

Try as,

let userOptions = (KeychainWrapper.standard.object(forKey: "userOptions").unsafelyUnwrapped as! [[String]]).joined().joined(separator: " ") )

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