我正在尝试保存一个类数组,到目前为止这是我的代码:
数组:
var person1 = person(name: "Bob", age: 22)
var person2 = person(name: "John", age: 10)
var array = [person1, person2]
自定义类:
import UIKit
class person: NSObject, NSCoding {
var name : String
var age : Int
init(name: String, age: Int) {
self.name = name
self.age = age
}
required init (coder aDecoder: NSCoder) {
name = (aDecoder.decodeObject(forKey: "name") as? String)!
age = (aDecoder.decodeObject(forKey: "age") as? Int)!
}
func encode(with aCoder: NSCoder) {
aCoder.encode(name, forKey: "name")
aCoder.encode(age, forKey: "age")
}
}
保存数组:
let SavedData = NSKeyedArchiver.archivedData(withRootObject: array)
let defaults = UserDefaults.standard
defaults.set(SavedData, forKey: "myPeople")
加载数组:
let saveddata = UserDefaults.standard.object(forKey: "myPeople") as? Data
if saveddata != nil{
array = (NSKeyedUnarchiver.unarchiveObject(with: saveddata!) as? [person])!
}
错误位于第age = (aDecoder.decodeObject(forKey: "age") as? Int)!
行
Interface Builder文件中的未知类iewripple。
答案 0 :(得分:1)
你不应该强迫打开。尝试获取
required init (coder aDecoder: NSCoder) {
name = (aDecoder.decodeObject(forKey: "name") as? String)!
age = (aDecoder.decodeObject(forKey: "age") as? Int)!
}
替换为
required init (coder aDecoder: NSCoder) {
name = aDecoder.decodeObject(forKey: "name") as? String ?? ""
age = aDecoder.decodeInteger(forKey: "age")
}
获取
let saveddata = UserDefaults.standard.object(forKey: "myPeople") as? Data
if saveddata != nil{
array = (NSKeyedUnarchiver.unarchiveObject(with: saveddata!) as? [person])!
}
替换为
if let data = UserDefaults.standard.object(forKey: "myPeople"),
let array = NSKeyedUnarchiver.unarchiveObject(with: data as! Data) as? [person] {
persons = array
}
我已经测试过了。代码工作正常。
let person1 = person(name: "Bob", age: 22)
let person2 = person(name: "John", age: 10)
var persons = [person1, person2]
// Save data
let data = NSKeyedArchiver.archivedData(withRootObject: persons)
let defaults = UserDefaults.standard
defaults.set(data, forKey: "myPeople")
// Load data
if let data = UserDefaults.standard.object(forKey: "myPeople"),
let array = NSKeyedUnarchiver.unarchiveObject(with: data as! Data) as? [person] {
persons = array
}
此外,通常将类名的第一个字母大写。您可以检查this是否有命名约定。
答案 1 :(得分:1)
发生错误是因为您正在对Int
进行编码,但解码失败的object
。
有专门的方法decodeInteger(forKey
。
请遵守命名约定,即类名以大写字母开头,变量名以小写字母开头。
class Person: NSObject, NSCoding {
要解决此问题,请将init(coder
方法更改为
required init(coder aDecoder: NSCoder) {
name = aDecoder.decodeObject(forKey: "name") as! String
age = aDecoder.decodeInteger(forKey: "age")
}
强制解包该字符串是100%安全的,因为该值始终编码为非可选字符。
保存数组
let savedData = NSKeyedArchiver.archivedData(withRootObject: array)
UserDefaults.standard.set(savedData, forKey: "myPeople")
加载数组
if let savedData = UserDefaults.standard.object(forKey: "myPeople") as? Data {
array = NSKeyedUnarchiver.unarchiveObject(with: savedData) as! [Person]
}
如果可选绑定as? Data
成功,强制解包在这种情况下也是安全的。