PFObject無法正確匹配TextField字符串（解析，Swift，iOS，Xcode 7 Beta）

我的主要目標是讓用戶在TextField中輸入一個zipcode，然後解析也會檢查數據庫，看看該zipcode是否匹配在數據庫中。如果是這樣，它將允許用戶註冊併發送println（「youre in」）。如果不是，它會打印（「你出去」）PFObject無法正確匹配TextField字符串（解析，Swift，iOS，Xcode 7 Beta）

這是我當前的代碼，以及我的Parse後端的樣子。

class checkAvailability: UIViewController, UITextFieldDelegate { 

@IBOutlet weak var zipCode: UITextField! 
@IBAction func checkAvailBtn(sender: AnyObject) { 
    checkZip() 
} 

func checkZip() { 
    let usersZipCode = zipCode.text 
    let query = PFQuery(className:"zipCodes") 
    query.findObjectsInBackgroundWithBlock { 
     (objects: [AnyObject]?, error: NSError?) -> Void in 

     if error == nil { 
      // The find succeeded. 
      print("Successfully retrieved \(objects!.count) zip codes.", terminator: "") 
      // Do something with the found objects 
      if let zipCodes = objects! as? [PFObject] { 
       if zipCodes.contains({ $0["zipCodes"] as? String == usersZipCode }) { 
        print("your in!") // transition to the new screen 

       } 
       else { 
        print("your out.") // do whatever 
       } 
      } 
     } else { 
      // Log details of the failure 
      print("Error: \(error!) \(error!.userInfo)", terminator: "") 
     } 
    } 
} 





override func viewDidLoad() { 
    super.viewDidLoad() 
    self.zipCode.delegate=self; 
} 
    //Allow only numbers 
    func textField(textField: UITextField, shouldChangeCharactersInRange range: NSRange, replacementString string: String) -> Bool { 
     return Int(string) != nil 
    } 



//Display Navbar 
override func viewWillAppear(animated: Bool) 
{ 
    self.navigationController?.navigationBarHidden = false 
} 

}

這裏是我的數據庫的圖像：