Swift 3 code update
<pre><code>class SignUp: UIViewController {

    @IBOutlet weak var buttonNameTxt: UITextField! @IBOutlet weak var buttonEmailTxt: UITextField! @IBOutlet weak var buttonPwdTxt: UITextField!

    override func viewDidLoad() { super.viewDidLoad()

    }

    @IBAction func buttonSignIn(_ sender: UIButton){

        let usermainname:NSString = buttonNameTxt.text! as NSString let username:NSString = buttonEmailTxt.text! as NSString let password:NSString = buttonPwdTxt.text! as NSString

        let myURL = NSURL(string: "https:\mev.com/api/login")
        let request = NSMutableURLRequest(url: myURL as! URL) request.httpMethod = "Post"

        let postString = "name = (usermainname) email = (username) &amp;passwod = (password) " request.httpBody = postString.data(using: String.Encoding.utf8)

        let task = URLSession.shared.dataTask(with: request as URLRequest) { data , response , error in

            do {

                let err: NSError? let json = try JSONSerialization.jsonObject(with: data!, options: .mutableContainers) as? NSDictionary

                print(json as Any)

                if let parseJSON = json { let resultValue = parseJSON["status"] as? String print ("result:(resultValue)")

                    var isUserRegister:Bool = false if resultValue == "success" {isUserRegister = true}

                    var messageToDisplay:String = parseJSON["massage"] as! String if isUserRegister {

                        messageToDisplay = parseJSON["massage"] as! String

                    }

                }

            } catch {

                print("error")
            }
        }
    }
}
</code></pre>

<p>This is error</p>

<blockquote>
  <p>2016-11-16 12:37:16.328505 MevicsPromo[12011:692688] [MC] System
  group container for systemgroup.com.apple.configurationprofiles path
  is
  /Users/HardBuf/Library/Developer/CoreSimulator/Devices/E3B4C6A4-A49D-4363-89D5-31931EA513A8/data/Containers/Shared/SystemGroup/systemgroup.com.apple.configurationprofiles
  2016-11-16 12:37:16.328782 MevicsPromo[12011:692688] [MC] Reading from
  private effective user settings. 2016-11-16 12:37:18.276331
  MevicsPromo[12011:692798] 0x60000014e4f0 Copy matching assets reply:
  XPC_TYPE_DICTIONARY { count = 1, transaction: 0, voucher = 0x0,
  contents = "Result" => : 29 } 2016-11-16 12:37:18.277030
  MevicsPromo[12011:692798] 0x608000357b80 Daemon configuration query
  reply: XPC_TYPE_DICTIONARY { count = 2, transaction: 0, voucher = 0x0,
  contents = "Dictionary" => { count = 1, transaction: 0, voucher = 0x0,
  contents = "ServerURL" => { count = 3, transaction: 0, voucher = 0x0,
  contents = "com.apple.CFURL.magic" =>
  C3853DCC-9776-4114-B6C1-FD9F51944A6D "com.apple.CFURL.string" => {
  length = 30, contents = "https:\mesu.apple.com/assets/" }
  "com.apple.CFURL.base" => : null-object } } "Result" => : 0 }
  2016-11-16 12:37:18.277318 MevicsPromo[12011:692798]
  http:\ru.stackoverflow.com/editing-help[MobileAssetError:29] Unable to
  copy asset information from https:\mesu.apple.com/assets/ for asset
  type com.apple.MobileAsset.TextInput.SpellChecker</p>
</blockquote>