Adapter pattern example

AdapterPatternExample.cs

class Program
    {
        static void Main(string[] args)
        {
            const string messageFormat = "{0} gave you a {1}, which is a type of {2}";

            // this operation expects to use a Character object
            Character _char;

            _char = new Character("Cecil");
            var item = _char.GetItem("Masamune");

            Console.WriteLine(messageFormat, _char.Name, item.Name, item.Class);

            // but what if the object was of type Npc?
            var npc = new Npc("Town Fence");
            _char = new NpcAdapter(npc);

            item = _char.GetItem("Hammer");
            Console.WriteLine(messageFormat, _char.Name, item.Name, item.Class);
        }

        // this will adapt the Npc object to work as if it were a Character object
        public class NpcAdapter : Character
        {
            private readonly Npc _npc;

            public NpcAdapter(Npc npc) : base(npc.Id)
            {
                _npc = npc;
                Name = npc.Id;
            }

            public override Item GetItem(string itemName)
            {
                return _npc.Items[itemName];
            }
        }

        public class Character
        {
            public string Name { get; set; }
            public List<Item> Backpack { get; set; }

            public Character(string name)
            {
                Name = name;

                // make some items
                Backpack = new List<Item>
                    {
                        new Item {Name = "Masamune", Class = "Sword"},
                        new Item {Name = "Desert Eagle", Class = "Gun"}
                    };
            }

            public virtual Item GetItem(string itemName)
            {
                return Backpack.Single(i => i.Name == itemName);
            }
        }

        public class Npc
        {
            public string Id { get; set; }
            public Dictionary<string, Item> Items { get; set; }

            public Npc(string id)
            {
                Id = id;

                // make some items
                Items = new Dictionary<string, Item>();
                Items.Add("Brie", new Item { Name = "Brie", Class = "Food"});
                Items.Add("Hammer", new Item { Name = "Hammer", Class = "Tool" });
            }
        }

        public class Item
        {
            public string Name { get; set; }
            public string Class { get; set; }
        }
    }