用Java或C＃反映工厂设计模式

用Java或C＃反映工厂设计模式

除非有特殊情况，否则我绝不会使用反射来实现Factory设计模式。下面的代码是实现工厂设计模式的一种糟糕方法。但是由于您想知道“如何”将反射用于工厂设计模式，因此以下示例：

namespace NaiveFactory{    public interface Shape    {        void Draw();    }    public class Circle : Shape    {        public void Draw() { Console.WriteLine("Drawing Circle"); }    }    public class Rectangle : Shape    {        public void Draw() { Console.WriteLine("Drawing Rectangle"); }    }    public class ShapeFactory    {        public static Shape GetShape<T>() where T : Shape        { return Activator.CreateInstance<T>();        }        public static Shape GetShape(string shapeName)        { var assembly = Assembly.GetExecutingAssembly(); var type = assembly.GetType(shapeName).FullName; return (Shape) Activator.CreateInstanceFrom(assembly.Location, type).Unwrap();        }    }    class Program    {        static void Main(string[] args)        { var shape = ShapeFactory.GetShape<Circle>(); var shape2 = ShapeFactory.GetShape("NaiveFactory.Rectangle"); shape.Draw(); shape2.Draw(); Console.ReadKey();        }    }}

编辑 根据@AlexeiLevenkov的建议，我在依赖注入中添加了一些内容，并

Shape

使用构造函数注入以及方法来实例化对象：

namespace NaiveFactory{    public interface IBoard    {        void InternalDraw(string str);    }    public class ConsoleBoard : IBoard    {        public void InternalDraw(string str) { Console.WriteLine(str); }    }    public class DebugBoard : IBoard    {        public void InternalDraw(string str) { Debug.WriteLine(str); }    }    public interface Shape    {        IBoard Board { get; set; }        void Draw();        void SetBoard(IBoard board);    }    public class Circle : Shape    {        public IBoard Board { get; set; }        public Circle()        {        }        public Circle(IBoard board)        { Board = board;        }        public void Draw() { Board.InternalDraw("Drawing Circle"); }        public void SetBoard(IBoard board)        { Board = board;        }    }    public class Rectangle : Shape    {        public IBoard Board { get; set; }        public Rectangle()        {        }        public Rectangle(IBoard board)        { Board = board;        }        public void Draw() { Board.InternalDraw("Drawing Rectangle"); }        public void SetBoard(IBoard board)        { Board = board;        }    }    public class ShapeFactory    {        private static Dictionary<Type, Type> _configurationData = new Dictionary<Type, Type>();        public static Shape GetShape<T>() where T : Shape        { return Activator.CreateInstance<T>();        }        public static void ConfigureContainer<T, U>()        { _configurationData.Add(typeof(T), typeof(U));        }        public static Shape GetShape_UsingConstructorInjection(string shapeName)        { var assembly = Assembly.GetExecutingAssembly(); var type = assembly.GetType(shapeName); var constructor = type.GetConstructor(_configurationData.Keys.ToArray()); if (constructor != null) {     var parameters = constructor.GetParameters();     return (from parameter in parameters where _configurationData.Keys.Contains(parameter.ParameterType)   select Activator.CreateInstance(_configurationData[parameter.ParameterType]) into boardObj   select (Shape) Activator.CreateInstance(type, boardObj)).FirstOrDefault(); } return null;        }        public static Shape GetShape_UsingSetBoardMethod(string shapeName)        { var assembly = Assembly.GetExecutingAssembly(); var type = assembly.GetType(shapeName); var shapeObj = (Shape) Activator.CreateInstance(type); if (shapeObj != null) {     shapeObj.SetBoard((IBoard) Activator.CreateInstance(_configurationData[typeof (IBoard)]));     return shapeObj; } return null;        }    }    class Program    {        static void Main(string[] args)        { ShapeFactory.ConfigureContainer<IBoard, ConsoleBoard>(); var shape = ShapeFactory.GetShape_UsingSetBoardMethod("NaiveFactory.Circle"); var shape2 = ShapeFactory.GetShape_UsingConstructorInjection("NaiveFactory.Rectangle"); shape.Draw(); shape2.Draw(); Console.ReadKey();        }    }}