用Alamofire传递令牌

Question

我有一个问题：我使用Alamofire从我的API成功检索了一个令牌，它是一个字符串。我想要做的是：“获取令牌（字符串）并将其放入另一个请求以从API获取一些JSON数据”

CURL： 卷曲-X GET -H“授权：令牌5f1884848”http://myurl.com

这就是我得到令牌的原因：

 let parameters = [
        "username" : usernameLabel.text!,
        "password" : passwordLabel.text!
    ]

    let credentialData = "\(usernameLabel.text):\(passwordLabel.text)".dataUsingEncoding(NSUTF8StringEncoding)!

    let base64Credentials = credentialData.base64EncodedStringWithOptions([])

    let headers = ["Authorization": "Basic \(base64Credentials)"]

    Alamofire.request(.POST, requestString, parameters: parameters, encoding: .JSON, headers: headers)
        .responseJSON { response in switch response.result {

        case .Success(let JSON):
            print("Success with JSON: \(JSON)")

            let response = JSON as! NSDictionary

            //example if there is a token
            self.userToken = response.objectForKey("token") as! String?
            print(self.userToken)

            debugPrint(response)

        case .Failure(let error):
            print("Request failed with error: \(error)")



            }

    }

我试图以某种方式保存userToken变量：

    class ViewController: UIViewController {
var userToken : String?

但我的userToken var始终为nil