Decode from struct or class model to JSON String or Data

EncoderAndDecoder.swift

import UIKit
func newJSONDecoder() -> JSONDecoder {
    let decoder = JSONDecoder()
    if #available(iOS 10.0, OSX 10.12, tvOS 10.0, watchOS 3.0, *) {
        decoder.dateDecodingStrategy = .iso8601
    }
    return decoder
}

func newJSONEncoder() -> JSONEncoder {
    let encoder = JSONEncoder()
    if #available(iOS 10.0, OSX 10.12, tvOS 10.0, watchOS 3.0, *) {
        encoder.dateEncodingStrategy = .iso8601
    }
    return encoder
}

ExampleStructOrClass.swift

import UIKit
struct ExampleStructOrClass: Codable {
    var name: String
    var address: String
    var age: Int
    var isSingle: Bool
    var favourite: [String]

    init(name: String, address: String, age: Int, isSingle: Bool, favourite: [String]) {
        self.name = name
        self.address = address
        self.age = age
        self.isSingle = isSingle
        self.favourite = favourite
    }
  
    func jsonData() throws -> Data {
        return try newJSONEncoder().encode(self)
    }

    func jsonString(encoding: String.Encoding = .utf8) throws -> String? {
        return String(data: try self.jsonData(), encoding: encoding)
    }
}

Usage.swift

var data = ExampleStructOrClass(name: "Raditsan", address: "Indonesia", age: 26, isSingle: false, favourite: ["Game","Coding","Reading"])
do {
    print("jsonString \(try data.jsonString() ?? "")")
} catch let error {
    print(error.localizedDescription)
}

Output
jsonString {"age":26,"isSingle":false,"favourite":["Game","Coding","Reading"],"name":"Raditsan","address":"Indonesia"}