Use of swift basic codable (jsonencoder jsondecoder)

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Codable Source code address

Preface

Codable The use of is generally used to store the data of the model , The model passes before storage Codable convert to data, Then take it out and pass data Convert to the corresponding model ,2. Add the use of route jump controller to change the model from A The controller is passed to B controller . It needs to be converted into binary . Restore the model after passing it back

On the subject

Use Codable Model of , The model needs to be followed Codable agreement .

If the model is nested with the model , Every model should also follow Codable agreement

for instance ：

import Foundation

enum TimelineMediaType: Int, Codable {
    
    case unknown
    case images
    case video
}

import Foundation

public enum UserStatus: Int, Codable {
    
    case none = 0 //  Unknown 
    case free = 1 //  Free 
    case calling = 2 //  Talking about 
    case resting = 3 //  Don't disturb 
    case hide = 4 //  stealth 
    case offline = 6 //  offline 
    
    public static func fromInt(_ value: Int) -> UserStatus {
    
        switch value {
    
        case 1: return .free
        case 2: return .calling
        case 3: return .resting
        case 4, 5: return .hide
        case 6, 7: return .offline
        default: return .none
        }
    }
    
    public var description: String {
    
        switch self {
    
        case .none: return ""
        case .free: return " Free "
        case .calling: return " Talking about "
        case .resting: return " Don't disturb "
        case .hide: return " stealth "
        case .offline: return " offline "
        }
    }
}

import Foundation

struct GreetingSelectionCache: Codable {
    
    var textID: Int64 = 0
    var voiceID: Int64 = 0
    var pictureID: Int64 = 0
}

import Foundation

class TimelineDetailModel: Codable {
    
    var timelineDetailType: TimelineMediaType
    var onlineState: UserStatus
    var title: String
    var cache: GreetingSelectionCache

    init(
       _ timelineDetailType: TimelineMediaType = .unknown,
       _ onlineState: UserStatus = .none,
       _ title: String = "",
       _ cache: GreetingSelectionCache = GreetingSelectionCache(textID: 0, voiceID: 0, pictureID: 0)
    ) {
    
        self.timelineDetailType = timelineDetailType
        self.onlineState = onlineState
        self.title = title
        self.cache = cache
    }

}

Use ：

override func viewDidLoad() {
    
    super.viewDidLoad()
    view.backgroundColor = .white
    
    let JSONEncoderModel = TimelineDetailModel()
    JSONEncoderModel.timelineDetailType = .images
    JSONEncoderModel.onlineState = .calling
    JSONEncoderModel.title = "fenghanxu"
    let cache = GreetingSelectionCache(textID: 1, voiceID: 2, pictureID: 3)
    JSONEncoderModel.cache = cache
    guard let data = try? JSONEncoder().encode(JSONEncoderModel) else {
     return }
    
    let JSONDecoderModel = try? JSONDecoder().decode(TimelineDetailModel.self, from: data)
    print("timelineDetailType: \(String(describing: JSONDecoderModel?.timelineDetailType))")
    print("onlineState: \(String(describing: JSONDecoderModel?.onlineState))")
    print("title: \(String(describing: JSONDecoderModel?.title))")
    print("cache: \(String(describing: JSONDecoderModel?.cache))")
    
}

Print the results ：

timelineDetailType: Optional(SwiftDemol.TimelineMediaType.images)
onlineState: Optional(SwiftDemol.UserStatus.calling)
title: Optional("fenghanxu")
cache: Optional(SwiftDemol.GreetingSelectionCache(textID: 1, voiceID: 2, pictureID: 3))