Question

我的代码读取文本文件并将文件内容存储在数组中。我在下一步遇到了麻烦;将数组的内容传输到Core Data。 .txt文件只是一个简短的水果列表。该实体是＆＃34; Fruit＆＃34;属性是＆＃34; fruitname＆＃34;。

打印时只显示最后一个数组元素。这是我的代码： -

    import UIKit
    import CoreData

    class ViewController: UIViewController {

    override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.


    // STORE .TXT FILE IN ARRAY.....
    let bundle = NSBundle.mainBundle()
    let fruitList = bundle.pathForResource("List of Fruits", ofType: "txt")

    let fruitArray = String(contentsOfFile: fruitList!, encoding: NSUTF8StringEncoding, error: nil)!.componentsSeparatedByString("\r")


    for x in fruitArray {
        println(x)

    }

    // STORE FRUIT-ARRAY IN CORE DATA......
    var appDel = UIApplication.sharedApplication().delegate as AppDelegate

    var context : NSManagedObjectContext! = appDel.managedObjectContext!

    var newFruit = NSEntityDescription.insertNewObjectForEntityForName("Fruit", inManagedObjectContext: context) as NSManagedObject

    for fruit in fruitArray {

        newFruit.setValue(fruit, forKey: "fruitname")
    }

    context.save(nil)


    // RETRIEVE AND PRINT STORED VALUES....
    var request = NSFetchRequest(entityName: "Fruit")
    request.returnsObjectsAsFaults = false

    var results = context.executeFetchRequest(request, error: nil)

    println(results)

}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}

}

这是两个println语句的输出....

//打印fruitArray 苹果杏香蕉覆盆子黑莓蓝莓椰子酸果蔓日期火龙果图葡萄番石榴甘露猕猴桃柠檬酸橙荔枝芒果瓜橙子番木瓜菠萝覆盆子杨桃草莓西瓜

//打印核心数据

可选（........ fruitname =西瓜; }）]

有人可以帮助确保fruitArray中的所有内容都保存在核心数据中吗？提前谢谢。

Answer 1

您只创建了一个newFruit。因此，您的for fruit in fruitArray循环只是反复重新分配fruitname属性。

将您的代码更改为：

for fruit in fruitArray {
  var newFruit = NSEntityDescription.insertNewObjectForEntityForName ("Fruit", 
     inManagedObjectContext: context) as NSManagedObject

  newFruit.setValue(fruit, forKey: "fruitname")
}

如何在核心数据中存储数组（Swift）

1 个答案: