How to take a matrix (List<List<>>()) from a Json?

Unity Engine
1

I have this class:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

[System.Serializable]
public class Map
{
    public int widht;
    public int height;
    public List<List<string>> box;
    public List<List<bool>> exploited;
    public int num_diggers;

    public Map()
    {

    }
    public void printContent()
    {

    }

    public void actualizarDimensiones(Dimensiones dimension)
    {

    }
}

and I am trying to get the dataa from that JSON:

{“widht”:10,
“height”:10,
“box”:[[“H”,“B”,“B”,“B”,“B”,“B”,“B”,“B”,“B”,“W”],[“B”,“B”,“B”,“B”,“B”,“B”,“B”,“B”,“B”,“B”],[“B”,“B”,“B”,“B”,“B”,“B”,“B”,“B”,“B”,“B”],[“B”,“B”,“B”,“B”,“B”,“B”,“B”,“B”,“B”,“B”],[“B”,“B”,“B”,“B”,“B”,“W”,“B”,“B”,“B”,“B”],[“B”,“B”,“B”,“B”,“W”,“W”,“F”,“B”,“B”,“B”],[“B”,“B”,“B”,“B”,“B”,“F”,“F”,“B”,“B”,“B”],[“B”,“B”,“B”,“B”,“B”,“B”,“B”,“F”,“P”,“P”],[“B”,“B”,“B”,“B”,“B”,“B”,“B”,“P”,“M”,“M”],[“W”,“B”,“B”,“B”,“B”,“B”,“B”,“P”,“M”,“M”]],
“exploited”:[[false,false,false,false,false,false,false,false,false,false],[false,false,false,false,false,false,false,false,false,false],[false,false,false,false,false,false,false,false,false,false],[false,false,false,false,false,false,false,false,false,false],[false,false,false,false,false,false,false,false,false,false],[false,false,false,false,false,false,false,false,false,false],[false,false,false,false,false,false,false,false,false,false],[false,false,false,false,false,false,false,false,false,false],[false,false,false,false,false,false,false,false,false,false],[false,false,false,false,false,false,false,false,false,false]],
“num_diggers”:1,
“diggers”:[{“golds”:[ ],
“id”:“0”,
“x”:1,
“y”:0}],
“golds”:[ ]}

but I can’t take the values of “box” and “exploited” witch are matrix. I am using the JsonUtility of Unity.

2

What does that means? What is shown in the debugger for that fields after deserialization? May be it will be of type int[ ][ ], not list<list> ?

3

JsonUtility can not handle nested Lists, but here is an example of what you can do to work around this issue :slight_smile:

3 Likes
4

oh thanks, I will try that!

5

Ok I changed my code and now looks like this:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

[System.Serializable]
public class Map
{
    public int widht;
    public int height;
    public List<StringListWrapper> box;
    public List<StringListWrapper> exploited;
    public int num_diggers;

    public Map()
    {

    }
    public void printContent()
    {
        Debug.Log("Width: " + widht);
        Debug.Log("Height: " + height);
        Debug.Log(box[0].getElement(0));
    }

    public void actualizarDimensiones(Dimensiones dimension)
    {
        Debug.Log("Width: " + dimension.widht);
        Debug.Log("Height: " + dimension.height);
        box = new List<StringListWrapper>(dimension.widht);
        for(int i = 0; i < dimension.widht; i++)
        {
            box.Add(new StringListWrapper(dimension.height));
        }
    }
}

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

[System.Serializable]
public class StringListWrapper
{
    List<string> myList;

    public StringListWrapper(int tama)
    {
        myList = new List<string>(tama);
        for(int i = 0; i < tama; i++)
        {
            myList.Add("");
        }
    }
    public string getElement(int index)
    {
        return myList[index];
    }
}

but when I use

mapa = new Map();
JsonUtility.FromJsonOverwrite(msg,mapa);JsonUtility.FromJsonOverwrite(msg,mapa);

My “box” attribute has nothing. What could be wrong now?

6

Did you changed the json according to your new structure?

7

I can’t change the JSON, is a JSON that I have been given and I need to read it. What’s wrong in the JSON?

8

You changed data structure and now it contains a class. But there’s still array in the json. It will not work. If you really can’t change the json, then i suggest you download Newtonsoft Json plugin and use it instead of unity serializer. But it’s easier to just change json

9

As I said I can’t change the Json so I will try to use the plugin you said or I will look for something in the asset store.
Thank you

10

Perfect!, It works Newtonsoft Json. There is an asset in the asset store called “json.net” that implements that library and it works perfect with a List<List>
Thank you!