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Protocollum Codable hereditates ex Decodable & Encodable

//
// Test1.swift
// TestDemo
//
// Creatum admin in 2024/7/9.
//

import Foundation

struct Player{
    var name:String
    var highScore:Int = 0
    var history:[Int] = []
    var address:Address?
    var birthday:Date?
    
    init(name: String) {
        self.name = name
    }
    
}

extension Player{
    mutating func updateScore(_ newScore:Int){
        history.append(newScore)
        if(highScore < newScore){
            highScore = newScore
        }
    }
}
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// Codable hereditates de Decodable & Encodable
/*

Codabile compositum est protocolla in Celeritate ad obiectivam serializationem et deserializationem simpliciorem. Constat ex Encodable et Decodable, quae obiectis ab externis repraesentationibus (ut JSON) respective ad objecta encode et decodere solent. Exsequendo Codable facile possumus rationes consuetudinis ad formas sicut JSON convertere.

*/

extension Player:Codable{
    /*
     如果 JSON 中的键与结构体中的属性名称不一致，可以使用 CodingKeys 枚举来定义自定义的键映射
     */
    enum CodingKeys:String,CodingKey{
        case name
        case highScore
        case address
        case birthday
        case history = "history1"
    }
}
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/*
Codable etiam operatur cum nidificatione genera
*/

struct Address:Codable{
    var street:String
    var citty:String
    var zipCode:String
}
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func test111(){
    var player = Player(name: "John")
    player.address = Address(street: "宝田一路", citty: "深圳", zipCode: "2212")
    player.birthday = Date(timeIntervalSince1970: 25 * 365 * 24 * 60 * 60)
    player.updateScore(121)
    player.updateScore(134)
    /*
     默认情况下，JSONEncoder 和 JSONDecoder 对日期的处理方式可能不符合需求，可以自定义日期格式
     */
    let formatter = DateFormatter()
    formatter.dateFormat = "yyyy-MM-dd"
    
    let encoder = JSONEncoder()
    encoder.dateEncodingStrategy = .formatted(formatter)
    let jsonData = try? encoder.encode(player)
    guard let jsonData = jsonData else{
        print("json data is nil")
        return
    }
    let jsonStr = String(data: jsonData, encoding: .utf8)
    guard let jsonStr = jsonStr else{
        print("json 数据编码失败")
        return
    }
    print("player 转json 字符串 : " + jsonStr)
    let decoder = JSONDecoder()
    decoder.dateDecodingStrategy = .formatted(formatter)
    guard let jsonDataDe = jsonStr.data(using: .utf8) else {
        print("json DataDe is null")
        return
    }
    
    //解码异常处理和打印
    var user :Player?
    do {
        user = try decoder.decode(Player.self, from: jsonDataDe)
    } catch let DecodingError.dataCorrupted(context) {
        print(context)
    } catch let DecodingError.keyNotFound(key, context) {
        print("Key '(key)' not found:", context.debugDescription)
        print("codingPath:", context.codingPath)
    } catch let DecodingError.valueNotFound(value, context) {
        print("Value '(value)' not found:", context.debugDescription)
        print("codingPath:", context.codingPath)
    } catch let DecodingError.typeMismatch(type, context)  {
        print("Type '(type)' mismatch:", context.debugDescription)
        print("codingPath:", context.codingPath)
    } catch {
        print("Error: ", error)
    }
    guard let user = user else{
        print("user is null")
        return
    }
    print("name:" + user.name + ",score:" + "(user.highScore)")
    
    
    
}
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