Question Getting exception link for my project included

This is the SaveLoad script :

Code (csharp):

1.  
2. using System;
3. using System.Collections;
4. using System.Collections.Generic;
5. using System.IO;
6. using System.Linq;
7. using UnityEngine;
8. using UnityEngine.UI;
9.  
10. public class SaveLoad : MonoBehaviour
11. {
12.    public List<Transform> objectsToSave = new List<Transform>();
13.    public Button saveButton;
14.  
15.    private void Awake()
16.    {
17.        SaveSystem.Init();
18.    }
19.  
20.    public void Save()
21.    {
22.        SaveGame saveGame = new SaveGame();
23.        saveGame.saveObjects = new List<SaveObject>();
24.        SaveObject saveObject = new SaveObject();
25.        for (int i = 0; i < objectsToSave.Count; i++)
26.        {
27.            saveObject.gameObjectInstanceID = objectsToSave[i].gameObject.GetInstanceID();
28.            var x = objectsToSave[i].GetComponents<Component>();
29.            var stateQueryComponent = x.Where(component => component is IStateQuery).ToList();
30.            List<KeyToValue> componentsState = new List<KeyToValue>();
31.            foreach (var z in stateQueryComponent)
32.            {
33.                var w = z as IStateQuery;
34.                componentsState.Add(new KeyToValue(w.UniqueId.ToString(), w.GetState()));
35.            }
36.  
37.            saveObject.position = objectsToSave[i].position;
38.            saveObject.rotation = objectsToSave[i].rotation;
39.            saveObject.scaling = objectsToSave[i].localScale;
40.  
41.            saveObject.componentsState = componentsState;
42.            saveGame.saveObjects.Add(saveObject);
43.  
44.            string json = JsonUtility.ToJson(saveObject);
45.  
46.            SaveSystem.Save(json);
47.        }
48.    }
49.  
50.    public void Load()
51.    {
52.        Dictionary<int, Transform> instanceIdToObject = objectsToSave
53.            .ToDictionary(o => o.GetInstanceID(), o => o);
54.        var saveString = SaveSystem.Load();
55.        if (saveString != null)
56.        {
57.            SaveGame saveGame = JsonUtility.FromJson<SaveGame>(saveString);
58.            foreach (var saveObject in saveGame.saveObjects)
59.            {
60.                List<KeyToValue> loadedComponents = saveObject.componentsState;
61.                var objectToSetState = instanceIdToObject[saveObject.gameObjectInstanceID];
62.  
63.                objectToSetState.position = saveObject.position;
64.                objectToSetState.rotation = saveObject.rotation;
65.                objectToSetState.localScale = saveObject.scaling;
66.  
67.                var y = objectToSetState.GetComponents<Component>();
68.                var z = y.Where(component => component is IStateQuery).ToList();
69.                Dictionary<string, IStateQuery> zz = z.ToDictionary(sq => (sq as IStateQuery).UniqueId.ToString(), sq => sq as IStateQuery);
70.  
71.                foreach (KeyToValue keyvalue in loadedComponents)
72.                {
73.                    zz[keyvalue.Key].SetState(keyvalue.Value);
74.                }
75.            }
76.        }
77.    }
78. }
79.  

The exception is on line 56 : When reading back from the text file to the json :

Code (csharp):

1.  
2. SaveGame saveGame = JsonUtility.FromJson<SaveGame>(saveString);
3.  

This is how I'm saving the json to the file on the hard drive :

Code (csharp):

1.  
2. using System;
3. using System.Collections;
4. using System.Collections.Generic;
5. using System.IO;
6. using UnityEngine;
7.  
8. public static class SaveSystem
9. {
10.    private static readonly string SAVE_FOLDER = Application.dataPath + "/save_";
11.    public static void Init()
12.    {
13.        if (!Directory.Exists(SAVE_FOLDER))
14.        {
15.            Directory.CreateDirectory(SAVE_FOLDER);
16.        }
17.    }
18.  
19.    public static void Save(string saveString)
20.    {
21.        string fileName = Path.Combine(SAVE_FOLDER, "savegame.txt");
22.        File.AppendAllText(fileName, saveString);
23.  
24.    }
25.  
26.    public static string Load()
27.    {
28.        string fileName = Path.Combine(SAVE_FOLDER, "savegame.txt");
29.        string content = File.ReadAllText(fileName);
30.  
31.        return content;
32.    }
33. }
34.  

I have two objects that I save it's info :



I'm not sure why it's giving the exception error and how to resolve it. It happens when trying to load back the saved game not when saving.

 

That's exactly your problem.

It's expecting a single JSON object, but your file has two top-level JSON objects. It's happening because when you save your data, you're appending instead of overwriting. This

Code (CSharp):

1. File.AppendAllText(fileName, saveString);

should be

Code (CSharp):

1. File.WriteAllText(fileName, saveString);

 

In the Save method in the SaveLoad script I'm doing :

Code (csharp):

1.  
2. saveGame.saveObjects.Add(saveObject);
3.  

It's adding the saveObject to a List.

But then in the Load using a break point on this line I see the saveObjects Listi s empty :

Code (csharp):

1.  
2. foreach (var saveObject in saveGame.saveObjects)
3.  

Why it's empty on the load ?

 

I don't really have the time right now to read and understand all that code, but:

Just wrap your objects in another object that has a list and serialize that:

Code (CSharp):

1. public class Wrapper {
2.   public List<TypeThatINeedToSaveMultipleOf> Data;
3. }