How to produce JSON file with C#, then read it back?

Unity Engine
1

Hello!
So I have a C# script which literally does nothing, and I can’t figure out why.

public TextAsset jsonFile;
    Item item = new Item();
    public string contents;

    void Start()
    {
        item.coin = new ItemData();
        item.coin.chance = 20.0f;
        item.coin.minDepth = 0.2f;
        item.coin.maxDepth = 6.7f;

        contents = JsonUtility.ToJson(item, true); // contents = {}
        Debug.Log("contents: " + contents); //contents: {}


        loadData();
    }

    void loadData()
    {
        item = JsonUtility.FromJson<Item>(contents);

        Debug.Log("loadData: " + item.coin.chance + " " + item.coin.minDepth + " " + item.coin.maxDepth); //NullReferenceException: Object reference not set to an instance of an object
    }

    [System.Serializable]
    public class ItemData
    {
        public float chance { get; set; }
        public float minDepth { get; set; }
        public float maxDepth { get; set; }
    }

    public class Item
    {
        public ItemData coin { get; set; }
    }

And my desired JSON output is:

{
    "coin":{
        "chance": 20.0,
        "mindepth": 0.2,
        "maxDepth": 6.7
    },
    "coinSmall":{
        "chance": 40.0,
        "mindepth": 0.2,
        "maxDepth": 6.7
    },
    "coinBig":{
        "chance": 40.0,
        "mindepth": 3.2,
        "maxDepth": 9.5
    }
    // Much more coin.
}

So, how could I achieve it? I’m not familiar with C#, I’m learning it now. In python, and Java I can do it, but in C# OMG I can’t.
Please help me!!

2

You should be more clear on the problem. You specifically said this code “literally does nothing”, but then I see in the comments of your code that the attempt to call Debug.Log is producing a NullReferenceException?

Anyway, you haven’t shown the code for Item, but the most likely problem is that you haven’t made the class serializable. Look into the Serializable attribute. Make sure that “contents” on line 12 ends up having the string value you expect, otherwise there’s obviously no reason to try to load an empty string.

3

Thanks! You helped me even with this kind of small clarification!