نموذج التصميم وزن الذبابة

public interface IFlyweight { void Load(string filename); void Display(PaintEventArgs e, int row, int col); }

public struct Flyweight : IFlyweight { // Intrinsic state Image pThumbnail; public void Load(string filename) { pThumbnail = new Bitmap(@"E:\wallpapers\" + filename).GetThumbnailImage(100, 100, null, new IntPtr()); } public void Display(PaintEventArgs e, int row, int col) { e.Graphics.DrawImage(pThumbnail, col * 100 + 10, row * 130 + 40, pThumbnail.Width, pThumbnail.Height); } }

public class FlyweightFactory { // Keeps an indexed list of IFlyweight objects in existence Dictionary<string, IFlyweight> flyweights =new Dictionary<string, IFlyweight>(); public FlyweightFactory() { flyweights.Clear(); } public IFlyweight this[string index] { get { if (!flyweights.ContainsKey(index)) flyweights[index] = new Flyweight(); return flyweights[index]; } } }

class Client { // Shared state - the images static FlyweightFactory album = new FlyweightFactory(); // Unshared state - the groups static Dictionary<string, List<string>> allGroups = new Dictionary<string, List<string>>(); public void LoadGroups() { var myGroups = new[] { new {Name = "FirstGroup", Members = new [] {"1.jpg", "2.jpg","3.jpg", "4.jpg"}}, new {Name = "SecondGroup", Members = new [] {"5.jpg","6.jpg","7.jpg", "8.jpg"}}, new {Name = "ThirdGroup", Members = new [] {"9.jpg", "10.jpg"}} }; // Load the Flyweights, saving on shared intrinsic state foreach (var g in myGroups) { // implicit typing allGroups.Add(g.Name, new List<string>()); foreach (string filename in g.Members) { allGroups[g.Name].Add(filename); album[filename].Load(filename); } } } public void DisplayGroups(Object source, PaintEventArgs e) { // Display the Flyweights, passing the unshared state int row = 0; foreach (string g in allGroups.Keys) { int col = 0; e.Graphics.DrawString(g, new Font("Arial", 16), new SolidBrush(Color.Black), new PointF(0, row * 130 + 10)); foreach (string filename in allGroups[g]) { album[filename].Display(e, row, col); col++; } row++; } } }

public partial class Window : Form { public Window() { InitializeComponent(); this.Height = 600; this.Width = 600; this.Text = "Picture Groups"; Client client = new Client(); client.LoadGroups(); this.Paint+= new PaintEventHandler(client.DisplayGroups); } static void Main() { Application.Run(new Window()); } }