Writing an class array to disk?

Question

 using UnityEngine;
 using System.Collections;
 
 public class ItemData : MonoBehaviour {
 
     void Start (){
 
     Item[] ItemDatabase = {
             new Item ("Baseball", "This a baseball", 5),
             new Item ("Ladder", "You can climb this", 5),
             new Item ("Radio", "Plays sounds", 5),
             new Item ("Book", "You can read this", 5) 
         };
 }
 
 
     class Item {
 
         public string _Name {get;set;}
         public string _Description {get;set;}
         public float _Value {get;set;}
         
         public Item (string Name, string Description, float Value)
         {
             _Name = Name; _Description = Description; _Value = Value;
         }
     }
 
 }

What is the easiest and most beginner friendly way to save and load that array to the disk locally?

Answer 1

You can use a BinaryFormatter.

Create an instance of a simple class which acts as your "save game" and holds all data that will be saved.

 [System.Serializable]
 public class Game {
      public string savegameName = "New Save Game",
      public ItemData.Item[] itemArray
 
 }

create the instance (in this case, done in your own script as it uses the ItemDataBase variable):

 Game newSaveGame = new Game() {
      savegameName = "My Saved Game";
      itemArray = ItemDatabase;
 
 };

Call the Save function and pass it the Game instance:

 SaveLoad.Save(newSaveGame);

To load, call the Load function and pass it the name of the saved file, it will return a deserialized Game instance which you can use to access the itemArray variable etc. in it.

 Game loadedGame = SaveLoad.Load("My Saved Game");

The SaveLoad static class:

 using UnityEngine;
 using System.Collections;
 using System.Collections.Generic;
 using System.Runtime.Serialization.Formatters.Binary;
 using System.IO;
 using System.Runtime.Serialization;
 //I don't remember which of these are necessary and which are not
 
 public static class SaveLoad {
 
 
     //it's static so we can call it from anywhere
     public static void Save(Game saveGame) {
         
         BinaryFormatter bf = new BinaryFormatter();
 
         //Application.persistentDataPath is a string, so if you wanted you can put that into debug.log if you want to know where save games are located
         FileStream file = File.Create (Application.persistentDataPath + saveGame.savegameName + ".sav"); //you can call it anything you want
         bf.Serialize(file, saveGame);
         file.Close();
         Debug.Log("Saved Game: " + saveGame.savegameName);
 
     }    
     
     public static Game Load(string gameToLoad) {
         if(File.Exists(Application.persistentDataPath + gameToLoad + ".sav")) {
             BinaryFormatter bf = new BinaryFormatter();
 
             FileStream file = File.Open(Application.persistentDataPath + gameToLoad + ".sav", FileMode.Open);
             Game loadedGame = (Game)bf.Deserialize(file);
             file.Close();
             Debug.Log("Loaded Game: " + loadedGame.savegameName);
             return loadedGame;
         }
         else {
             return null;
         }
     }
 }

Writing an class array to disk?

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