ios swift parse：保存到钥匙串并从钥匙串打印出数据并进行登录

Question

I implemented this code https://github.com/exchangegroup/keychain-swift to make use of the keychain. My question as a bloody beginner:

I use parse.com as API. I would like to save username, password and nickname to the keychain in order to login the user automatically. What works right now quite well, but when I try to print out the nickname with

let KeyChainNickname = "LocalNickname"
let currentNickname = TegKeychain.get(KeyChainNickname)
self.helloUserLabel.text = "Welcome \(currentNickname)"

I get this: Welcome Optional("MyNickname") which is the right nickname but surrounded by Optional("")

How can I print out the name without that Optional("")?

As I use parse.com I could also just pin the user data, where is really the difference between Parse local data store and the keychain? Beside the fact, that the keychain can by synced to other ios devices? Thats why I would prefer the keychain method.

Thanks so much!!

Answer 1

Add this ! in your code like this:

let currentNickname = TegKeychain.get(KeyChainNickname)!
self.helloUserLabel.text = "Welcome \(currentNickname)"

But you can use this ! if you are sure that currentNickname will defiantly get a value.

And your output will be "MyNickname" .

EDIT:

if let currentNickname = TegKeychain.get(KeyChainNickname){

self.helloUserLabel.text = "Welcome \(currentNickname)"
}

You can try this too.