无法在Swift3中检索正确保存的NSKeyArchived对象

Question

我无法检索到在Swift 3中保存为NSkeyed存档的对象，并且正在缩小我的头。对象保存成功是plist，但装回时返回零

这里是我使用的代码：

类本身保存为一个对象是相当容易：

import Foundation 

class ItemList:NSObject, NSCoding { 

    var name: String = "" //Name of the Item list 
    var contents: [Int] = [] //Ints referencing the CoreData PackItems 

    init (listname:String, ContentItems:[Int]) { 
     self.name=listname 
     self.contents=ContentItems 
    } 

    //MARK: NSCoding 
    public convenience required init?(coder aDecoder: NSCoder) { 
     let thename = aDecoder.decodeObject(forKey: "name") as! String 
     let thecontents = aDecoder.decodeObject(forKey: "contents") as! [Int] 
     self.init(listname: thename,ContentItems: thecontents) 
    } 

    func encode(with aCoder: NSCoder) { 
     aCoder.encode(self.name,forKey:"name") 
     aCoder.encode(self.contents, forKey: "contents") 
    } 

} 

加载和保存对象的代码：

class FileHandler: NSObject { 

    class func getDocumentsDirectory() -> URL { 
     let filemgr = FileManager.default 
     let urls = filemgr.urls(for: .documentDirectory, in: .userDomainMask) 
     let result:URL = urls.first! 
     return result 
    } 

    ///This returns the contents of the handed file inside the Documents directory as the object it was saved as. 
    class func getFileAsObject(filename:String) -> AnyObject? { 

     let path = getDocumentsDirectory().appendingPathComponent(filename) 

     if let result = NSKeyedUnarchiver.unarchiveObject(withFile: path.absoluteString) { 
      //Success 
      print("Loaded file '"+filename+"' from storage") 
      return result as AnyObject? 
     } else { 
      print("Error: Couldn't find requested object '"+filename+"' in storage at "+path.absoluteString) 
      return nil 
     } 
    } 

    ///This saves the handed object under the given filename in the App's Documents directory. 
    class func saveObjectAsFile(filename:String, Object:AnyObject) { 
     let data = NSKeyedArchiver.archivedData(withRootObject: Object) 
     let fullPath = getDocumentsDirectory().appendingPathComponent(filename) 

     do { 
      try data.write(to: fullPath) 
      print("Wrote file '"+filename+"' to storage at "+fullPath.absoluteString) 
     } catch { 
      print("Error: Couldn't write file '"+filename+"' to storage") 
     } 
    } 

} 

...最后，这是我做的叫了这一切：

let testobject:ItemList = ItemList.init(listname: "testlist", ContentItems: [0,0,1,2]) 

     FileHandler.saveObjectAsFile(filename:"Test.plist",Object:testobject) 
     let tobi = FileHandler.getFileAsObject(filename:"Test.plist") as! ItemList 

唉，我得到这个作为输出：

Wrote file 'Test.plist' to storage at file:///…/data/Containers/Data/Application/6747B038-B0F7-4B77-85A8-9EA02BC574FE/Documents/Test.plist 
Error: Couldn't find requested object 'Test.plist' in storage at file:///…/data/Containers/Data/Application/6747B038-B0F7-4B77-85A8-9EA02BC574FE/Documents/Test.plist 

请注意，这是我自己的输出 - 所以我做的（并已选中），该文件被正确创建。但它不会加载。谁能告诉我我做错了什么？

Answer 1

问题出在您传递给unarchiveObject(withFile:)的路径上。

变化：

if let result = NSKeyedUnarchiver.unarchiveObject(withFile: path.absoluteString) { 

到：

if let result = NSKeyedUnarchiver.unarchiveObject(withFile: path.path) { 

在一个侧面说明，你应该使用对称的API为你的写作和阅读的逻辑。在写入数据时，将根对象存档到Data对象，然后将Data对象写入文件。但是在阅读时，您可以直接取消存档给定文件路径的对象树。

请更改您的书写代码以使用archiveRootObject(_:toFile:)或更改读取代码以从文件加载Data，然后取消存档数据。你当前的代码有效（一旦你解决了路径问题）但它不一致。