How to create objects from SwiftyJSON

Question

I have a code, that parses JSON\'s list of questions and I can get every property. How can I iterate through the whole file and for each question create an object ?

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Answer 1

You can use SwiftyJSONModel which was specifically designed for this purpose. So in your case the model would be like this:

class Question: JSONObjectInitializable {
    enum PropertyKey: String {
        case level, questionText
        case answer1, answer2, answer3, answer4
        case correctAnswer, haveAnswered
    }

    var level : Int?
    var questionText : String?
    var answer1 : String?
    var answer2 : String?
    var answer3 : String?
    var answer4 : String?
    var correctAnswer : String?
    var haveAnswered : Bool = false

    required init(object: JSONObject) throws {
        level = object.value(for: .level)
        questionText = object.value(for: .questionText)
        answer1 = object.value(for: .answer1)
        answer2 = object.value(for: .answer2)
        answer3 = object.value(for: .answer3)
        answer4 = object.value(for: .answer4)
        correctAnswer = object.value(for: .correctAnswer)
        haveAnswered = object.value(for: .haveAnswered) ?? false
    }   
}

And then do like this:

let rootJSON = JSON(data: data)
let questions = rootJSON.arrayValue.flatMap { try? Question(json: $0) }

The framework gives you several nice features:

1. All the keys are stored in separated enum PropertyKey
2. No boilerplate as stringValue, intValue etc.
3. If JSON will be invalid, framework will give a verbose error and you will immediately see what exactly went wrong