How to serialize or convert Swift objects to JSON?

Question

This below class

class User: NSManagedObject {
  @NSManaged var id: Int
  @NSManaged var name: String
}

Needs to be converted to

{
    "id" : 98,
    "name" : "Jon Doe"
}

I tried manually passing the object to a function which sets the variables into a dictionary and returns the dictionary. But I would want a better way to accomplish this.

Answer 1

In Swift 4, you can inherit from the Codable type.

struct Dog: Codable {
    var name: String
    var owner: String
}

// Encode
let dog = Dog(name: "Rex", owner: "Etgar")

let jsonEncoder = JSONEncoder()
let jsonData = try jsonEncoder.encode(dog)
let json = String(data: jsonData, encoding: String.Encoding.utf16)

// Decode
let jsonDecoder = JSONDecoder()
let secondDog = try jsonDecoder.decode(Dog.self, from: jsonData)