如何使用NSUserDefaults在Swift中存储自定义类的数组？

Question

我有一个名为的自定义类Person,它在输入信息时存储有关某人的各种属性.

class Person {

    // Person dictionary variable
    var name: String?
    var age: String?
    var html_url: String?

    init(json: NSDictionary) { // Dictionary object
        self.name = json["name"] as? String
        self.age = json["age"] as? String
        self.html_url = json["html_url"] as? String // Location of the JSON file
    }
}

创建字典后,将其放入数组中.NSUserDefaults当点击按钮时,我在将阵列保存时遇到问题.

personArray.append(newPerson) // newPerson = dictionary of attributes


NSUserDefaults.standardUserDefaults().setObject(personArray, forKey: "personArray")
        NSUserDefaults.standardUserDefaults().synchronize()

我已经看过如何在NSUserDefaults中存储自定义对象和使用NSCoding将自定义SWIFT类保存到UserDefaults但是我没有运气并且发现它很难理解.

当我只是尝试保存到NSUserDefaults时,我被告知以下内容:

Attempt to set a non-property-list object (
    "PersonApp.Person"
) as an NSUserDefaults/CFPreferences value for key personArray

有人能通过NSUserDefaults帮我实际保存一系列自定义对象(自定义词典)吗？

Answer 1

您的Person类应如下所示:

斯威夫特3:

class Person : NSObject, NSCoding{

    // Person dictionary variable
    var name: String?
    var age: String?
    var html_url: String?

    init(json: NSDictionary) { // Dictionary object
        self.name = json["name"] as? String
        self.age = json["age"] as? String
        self.html_url = json["html_url"] as? String // Location of the JSON file
    }

    required init?(coder aDecoder: NSCoder) {

        self.name = aDecoder.decodeObjectForKey("name") as? String;
        self.age = aDecoder.decodeObjectForKey("age") as? String;
        self.html_url = aDecoder.decodeObjectForKey("html") as? String;
    }

    func encodeWithCoder(aCoder: NSCoder) {
        aCoder.encodeObject(self.name, forKey: "name");
        aCoder.encodeObject(self.age, forKey: "age");
        aCoder.encodeObject(self.html_url, forKey: "html");
    }
}

这里有一个从NSUserDefaults保存和检索数组的示例:

let p = Person()
p.name = "person1"
p.age = "12"
p.html_url = "www.google.ro"

let p2 = Person()
p2.name = "person2"
p2.age = "11"
p2.html_url = "www.google.ro"

let array = [p, p2]

let userDefaults = NSUserDefaults.standardUserDefaults()
userDefaults.setValue(NSKeyedArchiver.archivedDataWithRootObject(array), forKey: "persons")
userDefaults.synchronize()

let array : [Person]
array = NSKeyedUnarchiver.unarchiveObjectWithData(userDefaults.objectForKey("persons") as! NSData) as! [Person]
print("\(array[0].name)\(array[1].name)")

斯威夫特4:

class Person : NSObject, NSCoding{

    // Person dictionary variable
    var name: String?
    var age: String?
    var html_url: String?

    init(json: NSDictionary) { // Dictionary object
        self.name = json["name"] as? String
        self.age = json["age"] as? String
        self.html_url = json["html_url"] as? String // Location of the JSON file
    }

    required init?(coder aDecoder: NSCoder) {
        self.name = aDecoder.decodeObject(forKey: "name") as? String;
        self.age = aDecoder.decodeObject(forKey: "age") as? String;
        self.html_url = aDecoder.decodeObject(forKey: "html") as? String;
    }

    func encode(with aCoder: NSCoder) {
        aCoder.encode(self.name, forKey: "name");
        aCoder.encode(self.age, forKey: "age");
        aCoder.encode(self.html_url, forKey: "html");
    }
}

Answer 2

您需要实现NSCoding协议来存储自定义对象NSUserDefaults.看看这个例子http://nshipster.com/nscoding/