UserDefault などに class を保存するサンプル

NSCoding.swift

import Foundation
import ObjectMapper

public class User: NSObject, Mappable, NSCoding {
    public var id: Int!
    public var name: String!

    public required init?(map: Map) {
    }

    public func mapping(map: Map) {
        id <- map["id"]
        name <- map["name"]
    }

    required public init(coder: NSCoder) {
        id = coder.decodeObject(forKey: "id") as! Int
        name = coder.decodeObject(forKey: "name") as! String
    }

    public func encode(with aCoder: NSCoder) {
        aCoder.encode(id, forKey: "id")
        aCoder.encode(name, forKey: "name")
    }
}

let user = User()
user.id = 0
user.name = "name"
let data = NSKeyedArchiver.archivedData(withRootObject: user)
let unarchivedUser = NSKeyedUnarchiver.unarchiveObject(with: data) as! User