ios - 核心数据 swift : How to save and load data?

Question

我正在用 Swift 编写一个 iOS 游戏，我想在最后包含一个高分标签。我认为保存功能是正确的，但加载功能是给我带来问题的功能。我已经创建了一个实体(“BestScores”)和属性(“classicBestScoreTF”):

保存高分:

var bestscore25 = 1000
var score: int

func savescore() {    
    var appDel: AppDelegate = (UIApplication.sharedApplication().delegate as AppDelegate)
    var context:NSManagedObjectContext = appDel.managedObjectContext!
    var score25: AnyObject! = NSEntityDescription.insertNewObjectForEntityForName("BestScores", inManagedObjectContext: context) as NSManagedObject
    score25.setValue(score, forKey: "classicBestScoreTF")
    context.save(nil)
}

func loadscore() {
    var appDel: AppDelegate = (UIApplication.sharedApplication().delegate as AppDelegate)
    var context:NSManagedObjectContext = appDel.managedObjectContext!
    bestScore25 = valueForKey("classicBestScoreTF") as Int
}

func endgame() {

    if score > bestScore25 {
        savescore()
        loadscore()
        bestScoreLabel.text = "Best Score: \(bestScore25)"
    }

    if score < bestscore {            
        loadscore()
        bestScoreLabel.text = "Best Score: \(bestScore25)"
    }    
}

它不工作 :( 请帮助!

Answer 1

保存数据:

var person = NSEntityDescription.insertNewObjectForEntityForName("Person", 
inManagedObjectContext: self.managedObjectContext!) as Person
person.name = "Mary"
person.age = Float(arc4random() % 100)

var error : NSError? = nil
if !self.managedObjectContext!.save(&error) {
    NSLog("Unresolved error \(error), \(error!.userInfo)")
    abort()
}

加载数据:

var error: NSError? = nil
var fReq: NSFetchRequest = NSFetchRequest(entityName: "Frases")    
fReq.predicate = NSPredicate(format: "id contains[c] %@", String(day))
var sorter: NSSortDescriptor = NSSortDescriptor(key: "id" , ascending: false)
fReq.sortDescriptors = [sorter]
fReq.returnsObjectsAsFaults = false
let result : [AnyObject] = self.managedObjectContext!.executeFetchRequest(fReq, error:&error)!