Hi! I’m trying to create a save and load system for an inventory system I made. The way I’m trying to do it is serializing the list of Items (a serializable class) in binary format, but when I call the function “Save” located in the Inventory System script, it throws me an error, saying that “InventorySystem” is not serlialized, when it’s a Monobehaviour. I don’t know how to solve this problem, or even if this way is the propper way to do it. Please help me. 
Save Load System
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using System;
using System.Runtime.Serialization.Formatters.Binary;
using System.IO;
public static class SaveLoadSystem {
public static void SaveInventory (InventorySystem inventario){
BinaryFormatter bf = new BinaryFormatter ();
FileStream archivo = new FileStream (Application.persistentDataPath + "/inventario.sav", FileMode.Create);
InventoryData data = new InventoryData (inventario);
bf.Serialize (archivo, data);
archivo.Close ();
}
public static List<Items> LoadInventory (){
if (File.Exists (Application.persistentDataPath + "/inventario.sav")) {
BinaryFormatter bf = new BinaryFormatter ();
FileStream archivo = new FileStream (Application.persistentDataPath + "/inventario.sav", FileMode.Open);
InventoryData data = bf.Deserialize (archivo) as InventoryData;
archivo.Close ();
return data.itemsContenidos;
} else {
Debug.Log ("El archivo guardado no existe");
return new List<Items> ();
}
}
}
[System.Serializable]
public class InventoryData{
public List<Items> itemsContenidos;
public InventoryData (InventorySystem inventario){
itemsContenidos = new List<Items> ();
for (int i = 0; i < inventario.inventario.Count; i++) {
itemsContenidos.Add (inventario.inventario [i]);
}
}
}
Items Class
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public enum tiposItem {daga,espada,alabarda,pocionHP,pocionMana,armadura}
[System.Serializable]
public class Items {
public InventorySystem inventarioPerteneciente;
// GENERAL
public string nombre;
public string descripcion;
public Sprite sprite;
// CONSUMIBLES
public int cantidad;
// POCIONES
public int cantidadRecuperada;
// ARMADURAS
public float penalizacionAguante;
[Range(1,3)]
public int tier;
public bool sloteada;
public float vitalidad;
public float mitigacion;
// ARMAS
// int tier;
public bool isRare;
public int rareza;
public float critico;
public float fuerza;
public float velocidadDeAtaque;
public float espiritu;
public float ki;
public int nivel = 1;
public int nivelMax = 1;
public int experienciaActual;
public int experienciaTotal = 1000;
public int experienciaMaxBase = 1000;
public Items (int tier){
this.tier = tier;
}
public Items (int tier, bool isRare){
this.tier = tier;
this.isRare = isRare;
}
public virtual void Usar(){
Debug.Log ("Usando objeto base");
}
public virtual void ganarExp(int cantidad){
}
}
Inventory System
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class InventorySystem : MonoBehaviour {
public static InventorySystem script;
void Awake(){
script = this;
DontDestroyOnLoad (transform.gameObject);
}
public delegate void AccionesInventario ();
public event AccionesInventario ItemAdded; // Suscriptores: InventarioHUD.updateInventoryHUD
public event AccionesInventario ItemRemoved; // Suscriptores: InventarioHUD.updateInventoryHUD
public List<Items> inventario;
public int inventarioCount = 0;
public Estadisticas statsPlayer;
public List<Armas> armaEquipada;
public List<Armaduras> armaduraEquipada;
public void addItem(Items objeto){
if (inventario.Count < 20) {
inventario.Add (objeto);
objeto.inventarioPerteneciente = this;
inventarioCount++;
ItemAdded (); // Delegado añadir
} else {
Debug.Log ("Inventario lleno");
}
}
public void removeItem(Items objeto){
inventario.Remove (objeto);
inventarioCount--;
ItemRemoved (); // Delegado borrar
}
public void equiparArmadura(Armaduras armadura){
if (armaduraEquipada.Count == 0) {
armaduraEquipada.Add (armadura);
removeItem (armadura);
} else {
addItem (armaduraEquipada [0]);
armaduraEquipada.RemoveAt (0);
armaduraEquipada.Add (armadura);
removeItem (armadura);
}
changeStats ();
}
public void equiparArma(Armas arma){
if (armaEquipada.Count == 0) {
armaEquipada.Add (arma);
removeItem (arma);
} else {
addItem (armaEquipada [0]);
armaEquipada.RemoveAt (0);
armaEquipada.Add (arma);
removeItem (arma);
}
changeStats ();
}
// TESTING SAVE LOAD
public void Save(){
SaveLoadSystem.SaveInventory (this);
}
public void Load(){
List<Items> loadedInventario = SaveLoadSystem.LoadInventory ();
inventario.Clear ();
foreach (Items item in loadedInventario) {
inventario.Add (item);
}
}
}