Compartilhamento de tecnologia

한어Русский языкEnglishFrançaisIndonesianSanskrit日本語DeutschPortuguêsΕλληνικάespañolItalianoSuomalainenLatina

O protocolo Codable herda de Decodable & Encodable

//
// Teste1.swift
// TesteDemo
//
// Criado por admin em 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
        }
    }
}
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23

//Codificável herda de Decodable e Encodable
/*

Codable é uma combinação de protocolos em Swift para simplificar a serialização e desserialização de objetos. Consiste em Encodable e Decodable, que são usados ​​para codificar e decodificar objetos de representações externas (como JSON), respectivamente. Ao implementar Codable, podemos converter facilmente tipos personalizados em formatos como JSON.

*/

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"
    }
}
1
2
3
4
5
6
7
8
9
10
11
12

/*
Codable também funciona com tipos aninhados
*/

struct Address:Codable{
    var street:String
    var citty:String
    var zipCode:String
}
1
2
3
4
5

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)")
    
    
    
}
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59

1
2
3