Parse JSON into an array of objects

Question

I have the following serialized class:

[System.Serializable]
public class Question
{
    public string question;
    public List<string> answers;
    public string correct;

    public Question(string question, List<string> answers, string correct){
        this.question = question;
        this.answers = answers;
        this.correct = correct;
    }
}

And the following array of questions:

questions = new List<GameManager.Question>();
questions.Add(new GameManager.Question("2+2?", new List<string> { "4", "5", "6" }, "4"));
questions.Add(new GameManager.Question("2*2?", new List<string> { "1", "4", "8" }, "4"));
questions.Add(new GameManager.Question("2/2?", new List<string> { "0", "1", "2" }, "1"));

I need to store this information as jsonformat and load it to init the question game.

How I can load an array of questions using json?

You can use `NewtonSoft.JsonConvert.SerializeObject` and `Newtonsoft.JsonConvert.DeserializeObject` if you have that nuget package installed. Then just decorate your properties with a `JsonProperty` tag, documentation (https://www.newtonsoft.com/json/help/html/SerializingJSON.htm) — Ryan Wilson, Oct 10 '18 at 20:02
Have you tried looking online for C# libraries that allows you to work with JSON? If you haven't, you should do so before posing a question on Stack Overflow. If you have, you should explain what you've tried already, and why it hasn't met your requirements. — Serlite, Oct 10 '18 at 20:04
JsonUtility.ToJson(object) will convert your Question into a string in json format. — Everts, Oct 10 '18 at 20:28

score 1 · Answer 1 · answered Oct 10 '18 at 20:05

1

You can use newtonsoft.json to serialize and deserialize the objects. It is very simple to use. I think you have to install the nuget package.

Here is a post on how to serialize and save data in unity 3d: Post

answered Oct 10 '18 at 20:05

juliushuck

1,398
1
11
25

Aydin · Answer 2 · 2018-10-10T20:09:26.140

Here's a working example

void Main()
{
    var questions = new List<Question>();
    questions.Add(new Question("2+2?", new List<string> { "4", "5", "6" }, "4"));
    questions.Add(new Question("2*2?", new List<string> { "1", "4", "8" }, "4"));
    questions.Add(new Question("2/2?", new List<string> { "0", "1", "2" }, "1"));

    var json = JsonConvert.SerializeObject(questions, Newtonsoft.Json.Formatting.Indented);
    Console.WriteLine(json);
}

// Define other methods and classes here
public class Question
{
    public string question;
    public List<string> answers;
    public string correct;

    public Question(string question, List<string> answers, string correct)
    {
        this.question = question;
        this.answers = answers;
        this.correct = correct;
    }
}

Output

[
  {
    "question": "2+2?",
    "answers": [
      "4",
      "5",
      "6"
    ],
    "correct": "4"
  },
  {
    "question": "2*2?",
    "answers": [
      "1",
      "4",
      "8"
    ],
    "correct": "4"
  },
  {
    "question": "2/2?",
    "answers": [
      "0",
      "1",
      "2"
    ],
    "correct": "1"
  }
]

You can deserialize it back to a collection of questions by

var deserialized = JsonConvert.DeserializeObject<Question[]>(json);

I need to generate a Question array from a json file, not generating a json file from that array. — Lechucico, Oct 10 '18 at 20:07
@Lechucico Then you use `Newtonsoft.Json.DeserializeObject` where T is a `List`, please see my answer or comment for documentation. — Ryan Wilson, Oct 10 '18 at 20:09
Thanks @AydinAdn. Any idea on how to import JsonConvert package on Unity? — Lechucico, Oct 10 '18 at 20:19

score 0 · Answer 3 · answered Oct 10 '18 at 20:06

You can use NewtonSoft.Json.JsonConvert.SerializeObject and Newtonsoft.Json.JsonConvert.DeserializeObject<T> if you have that nuget package installed. Then just decorate your properties with a JsonProperty tag, documentation (https://www.newtonsoft.com/json/help/html/SerializingJSON.htm)

Parse JSON into an array of objects

3 Answers3