gistfile1.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;

namespace ConsoleApplication2
{
	enum GameObjectType
	{
		Room,
		Player,
		Enemey
	}

	interface IGameObject
	{
		GameObjectType Type { get; }

		void Load(BinaryReader reader);
		void Save(BinaryWriter writer);
	}

	class Room : IGameObject
	{
		public GameObjectType Type { get { return GameObjectType.Room; } }

		public string Name { get; set; }
		public string Description { get; set; }

		public void Load(BinaryReader reader)
		{
			Name = reader.ReadString();
			Description = reader.ReadString();
		}

		public void Save(BinaryWriter writer)
		{
			writer.Write(Name);
			writer.Write(Description);
		}
	}

	class Player : IGameObject
	{
		public GameObjectType Type { get { return GameObjectType.Player; } }

		public string Name { get; set; }
		public int Health { get; set; }

		public void Load(BinaryReader reader)
		{
			Name = reader.ReadString();
			Health = reader.ReadInt32();
		}

		public void Save(BinaryWriter writer)
		{
			writer.Write(Name);
			writer.Write(Health);
		}
	}

	class Enemey : IGameObject
	{
		public GameObjectType Type { get { return GameObjectType.Enemey; } }

		public string Name { get; set; }
		public int Health { get; set; }

		public void Load(BinaryReader reader)
		{
			Name = reader.ReadString();
			Health = reader.ReadInt32();
		}

		public void Save(BinaryWriter writer)
		{
			writer.Write(Name);
			writer.Write(Health);
		}
	}

	class Game
	{
		public Player Player { get; set; }
		public List<IGameObject> GameObjects { get; private set; }

		public Game()
		{
			GameObjects = new List<IGameObject>();
		}

		public void AddGameObject(IGameObject room)
		{
			GameObjects.Add(room);
		}
	}

	// {count of game objects}{room|player}{game object data}{room|player}{game object data}

	// {2}    {room} {room 1}{room 1 description} {player} {nelson}{100}
	// count  type   data                         type     data

	class GameFilePersistence
	{
		public void SaveGame(string filename, Game game)
		{
			using (var bw = new BinaryWriter(File.Open(filename, FileMode.OpenOrCreate)))
			{
				bw.Write(game.GameObjects.Count);

				foreach (var gameObject in game.GameObjects)
				{
					bw.Write((int)gameObject.Type);
					gameObject.Save(bw);
				}
			}
		}

		public Game LoadGame(string filename)
		{
			var game = new Game();

			using (var br = new BinaryReader(File.Open(filename, FileMode.Open)))
			{
				var gameObjectCount = br.ReadInt32();
				for (var i = 0; i < gameObjectCount; i++)
				{
					var type = (GameObjectType)br.ReadInt32();
					
					IGameObject obj = null;
					switch (type)
					{
						case GameObjectType.Room: obj = new Room(); break;
						case GameObjectType.Player: obj = game.Player = new Player(); break;
						case GameObjectType.Enemey: obj = new Enemey(); break;
					}

					obj.Load(br);
					game.AddGameObject(obj);
				}
			}

			return game;
		}
	}

	class Program
	{
		static void Main(string[] args)
		{
			var game = new Game();

			var room1 = new Room();
			room1.Name = "Room 1";
			room1.Description = "Room 1 description";

			var room2 = new Room();
			room2.Name = "Room 2";
			room2.Description = "Room 2 description";

			var player = new Player();
			player.Name = "Nelson";
			player.Health = 100;

			var e1 = new Enemey();
			e1.Name = "Blegh";
			e1.Health = 32;

			var e2 = new Enemey();
			e2.Name = "ASDASDAS";
			e2.Health = 423;

			game.Player = player;

			game.AddGameObject(player);
			game.AddGameObject(room1);
			game.AddGameObject(room2);
			game.AddGameObject(e1);
			game.AddGameObject(e2);

			var persistence = new GameFilePersistence();
			persistence.SaveGame("game1.game", game);

			var loadedGame = persistence.LoadGame("game1.game");
			foreach (var go in loadedGame.GameObjects)
			{
				var room = go as Room;
				if (room != null)
				{
					Console.WriteLine("Room: {0}", room.Name);
				}

				var thePlayer = go as Player;
				if (thePlayer != null)
				{
					Console.WriteLine("Player: {0}", thePlayer.Name);
				}

				var enemey = go as Enemey;
				if (enemey != null)
				{
					Console.WriteLine("Enemey: {0}", enemey.Name);
				}
			}

			Console.ReadKey();
		}
	}
}