public Guitar search(Guitar searchGuitar)
        {
            foreach (var guitar in guitars)
            {
                String builder = searchGuitar.getBuilder();
                if ((builder != null) && (!builder.Equals("")) &&
                    (!builder.Equals(guitar.getBuilder())))
                    continue;
                String model = searchGuitar.getModel();
                if ((model != null) && (!model.Equals("")) &&
                    (!model.Equals(guitar.getModel())))
                    continue;
                String type = searchGuitar.getType();
                if ((type != null) && (!searchGuitar.Equals("")) &&
                    (!type.Equals(guitar.getType())))
                    continue;
                String backWood = searchGuitar.getBackWood();
                if ((backWood != null) && (!backWood.Equals("")) &&
                    (!backWood.Equals(guitar.getBackWood())))
                    continue;
                String topWood = searchGuitar.getTopWood();
                if ((topWood != null) && (!topWood.Equals("")) &&
                    (!topWood.Equals(guitar.getTopWood())))
                    continue;
                return guitar;
            }

            return null;
        }
 public void addGuitar(String serialNumber, double price,
               String builder, String model,
               String type, String backWood, String topWood)
 {
     Guitar guitar = new Guitar(serialNumber, price, builder,
                                model, type, backWood, topWood);
     guitars.Add(guitar);
 }
        public void SearchGuitar()
        {
            Guitar whatErinLikes = new Guitar("", 0, "fender", "Stratocastor",
                                   "electric", "Alder", "Alder");

            Guitar guitar = inventory.search(whatErinLikes);
            if (guitar != null)
            {
               Debug.WriteLine("Erin, you might like this " +
                  guitar.getBuilder() + " " + guitar.getModel() + " " +
                  guitar.getType() + " guitar:\n   " +
                  guitar.getBackWood() + " back and sides,\n   " +
                  guitar.getTopWood() + " top.\nYou can have it for only $" +
                  guitar.getPrice() + "!");
            }
            else
            {
                Debug.WriteLine("Sorry, Erin, we have nothing for you.");
            }
        }