CSharp: Strategy Pattern

 

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/// <summary>   /// A simple file handlng class   /// Strategy Pattern 策略模式   ///20220918   /// geovindu,Geovin Du,涂聚文   /// </summary>   public class csFile   {       private string fileName;       StreamReader ts;       StreamWriter ws;       /// <summary>       ///       /// </summary>       private bool opened, writeOpened;       /// <summary>       ///       /// </summary>       public csFile()       {           init();       }       /// <summary>       ///       /// </summary>       private void init()       {           opened = false;           writeOpened = false;       }       /// <summary>       ///       /// </summary>       /// <param name="file_name"></param>       public csFile(string file_name)       {           fileName = file_name;           init();       }       /// <summary>       ///       /// </summary>       /// <param name="file_name"></param>       /// <returns></returns>       public bool OpenForRead(string file_name)       {           fileName = file_name;           try           {               ts = new StreamReader(fileName);               opened = true;           }           catch (FileNotFoundException)           {               return false;           }           return true;       }       /// <summary>       ///       /// </summary>       /// <returns></returns>       public bool OpenForRead()       {           return OpenForRead(fileName);       }       /// <summary>       ///       /// </summary>       /// <returns></returns>       public string readLine()       {           return ts.ReadLine();       }       /// <summary>       ///       /// </summary>       /// <param name="s"></param>       public void writeLine(string s)       {           ws.WriteLine(s);       }       /// <summary>       ///       /// </summary>       public void close()       {           if (opened)               ts.Close();           if (writeOpened)               ws.Close();       }       /// <summary>       ///       /// </summary>       /// <returns></returns>       public bool OpenForWrite()       {           return OpenForWrite(fileName);       }       /// <summary>       ///       /// </summary>       /// <param name="file_name"></param>       /// <returns></returns>       public bool OpenForWrite(string file_name)       {           try           {               ws = new StreamWriter(file_name);               fileName = file_name;               writeOpened = true;               return true;           }           catch (FileNotFoundException)           {               return false;           }       }   }

　　

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/// <summary> /// String Tokenizer class /// Strategy Pattern 策略模式 ///20220918 /// geovindu,Geovin Du,涂聚文 /// </summary> public class StringTokenizer {     private string data, delimiter;     private string[] tokens;     private int index;     /// <summary>     ///     /// </summary>     /// <param name="dataLine"></param>     public StringTokenizer(string dataLine)     {         init(dataLine, " ");     }     /// <summary>     ///     /// </summary>     /// <param name="dataLine"></param>     /// <param name="delim"></param>     private void init(String dataLine, string delim)     {         delimiter = delim;         data = dataLine;         tokens = data.Split(delimiter.ToCharArray());         index = 0;     }     /// <summary>     ///     /// </summary>     /// <param name="dataLine"></param>     /// <param name="delim"></param>     public StringTokenizer(string dataLine, string delim)     {         init(dataLine, delim);     }     /// <summary>     ///     /// </summary>     /// <returns></returns>     public bool hasMoreElements()     {         return (index < (tokens.Length));     }     /// <summary>     ///     /// </summary>     /// <returns></returns>     public string nextToken()     {         return nextElement();     }     /// <summary>     ///     /// </summary>     /// <returns></returns>     public string nextElement()     {         string s = tokens[index++];         while ((s.Length <= 0) && (index < tokens.Length))             s = tokens[index++];         return s;     } }

　　

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/// <summary> /// Command interface /// Strategy Pattern 策略模式 ///20220918 /// geovindu,Geovin Du,涂聚文 /// </summary> public interface Command {     void Execute(); }

　　

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/// <summary>   /// Selects which plot strategy to carry out   /// Strategy Pattern 策略模式   ///20220918   /// geovindu,Geovin Du,涂聚文   /// </summary>   public class Context   {       float[] x, y;       PlotStrategy plts;  //strategy selected goes here       /// <summary>       /// -----       /// </summary>       public void plot()       {           readFile();     //read in data           plts.plot(x, y);       }             /// <summary>       /// select bar plot       /// </summary>       public void setBarPlot()       {           plts = new BarPlotStrategy();       }          /// <summary>       /// select line plot       /// </summary>       public void setLinePlot()       {           plts = new LinePlotStrategy();       }       /// <summary>       ///       /// </summary>       public void readFile()       {           ArrayList xc = new ArrayList();           ArrayList yc = new ArrayList();             //reads data in from data file           csFile fl = new csFile("data.txt");           fl.OpenForRead();           string sline = fl.readLine();           while (sline != null)           {               int i = sline.IndexOf(" ");               if (i > 0)               {                   float tmp = Convert.ToSingle(sline.Substring(0, i));                   xc.Add(tmp);                   tmp = Convert.ToSingle(sline.Substring(i + 1));                   yc.Add(tmp);               }               sline = fl.readLine();           }           //copy into arrays from collections           float[] xp = new float[xc.Count];           float[] yp = new float[yc.Count];           for (int i = 0; i < xc.Count; i++)           {               xp[i] = (float)xc[i];               yp[i] = (float)yc[i];           }           x = xp;           y = yp;           fl.close();       }   }

　　

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/// <summary> /// Summary description for PlotStrategy. /// Strategy Pattern 策略模式 ///20220918 /// geovindu,Geovin Du,涂聚文 /// </summary> public abstract class PlotStrategy {     public abstract void plot(float[] x, float[] y); }

　　

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/// <summary> /// Summary description for LinePlotStrategy. /// Strategy Pattern 策略模式 ///20220918 /// geovindu,Geovin Du,涂聚文 /// </summary> public class LinePlotStrategy : PlotStrategy {       /// <summary>     ///     /// </summary>     /// <param name="x"></param>     /// <param name="y"></param>     public override void plot(float[] x, float[] y)     {         LinePlotForm lplt = new LinePlotForm();         lplt.Show();         lplt.plot(x, y);     } }

　　

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/// <summary> /// Summary description for BarPlotStrategy. /// Strategy Pattern 策略模式 ///20220918 /// geovindu,Geovin Du,涂聚文 /// </summary> public class BarPlotStrategy : PlotStrategy {     public override void plot(float[] xp, float[] yp)     {         BarPlotForm bplot = new BarPlotForm();         bplot.Show();         bplot.plot(xp, yp);     } }

　　

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/// <summary> /// Strategy Pattern 策略模式 ///20220918 /// geovindu,Geovin Du,涂聚文 /// </summary> public partial class BarButton : System.Windows.Forms.Button, Command {     /// <summary>     ///     /// </summary>     private Context contxt;     /// <summary>     ///     /// </summary>     /// <param name="ctx"></param>     public void setContext(Context ctx)     {         contxt = ctx;     }     public void Execute()     {         contxt.setBarPlot();         contxt.plot();     }       /// <summary>     ///     /// </summary>     public BarButton()     {         InitializeComponent();     }     /// <summary>     ///     /// </summary>     /// <param name="container"></param>     public BarButton(IContainer container)     {         container.Add(this);           InitializeComponent();     } }

　　

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/// <summary>  /// Strategy Pattern 策略模式  ///20220918  /// geovindu,Geovin Du,涂聚文  /// </summary>  public partial class LineButton : System.Windows.Forms.Button, Command  {      /// <summary>      ///      /// </summary>      private Context contxt;      /// <summary>      ///      /// </summary>      /// <param name="ctx"></param>      public void setContext(Context ctx)      {          contxt = ctx;      }      /// <summary>      ///      /// </summary>      public void Execute()      {          contxt.setLinePlot();          contxt.plot();      }      /// <summary>      ///      /// </summary>      public LineButton()      {          InitializeComponent();          this.Text = "Line plot";      }      /// <summary>      ///      /// </summary>      /// <param name="container"></param>      public LineButton(IContainer container)      {          container.Add(this);            InitializeComponent();      }  }

　　

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/// <summary>  /// Strategy Pattern 策略模式  ///20220918  /// geovindu,Geovin Du,涂聚文  /// </summary>  public partial class BarPlotForm : Form  {      protected float ymin, ymax, xfactor, yfactor;      protected float xpmin, xpmax, ypmin, ypmax, xp, yp;      private float xmin, xmax;      private int w, h;      protected float[] x, y;      private ArrayList colors;      protected Pen bPen;      protected bool hasData;      protected const float max = 1.0e38f;      /// <summary>      ///      /// </summary>      /// <param name="xp"></param>      /// <param name="yp"></param>      public void plot(float[] xp, float[] yp)      {          x = xp;          y = yp;          setPlotBounds();    //compute scaling factors          hasData = true;          pic.Refresh();      }      /// <summary>      ///      /// </summary>      public void findBounds()      {          xmin = max;          xmax = -max;          ymin = max;          ymax = -max;            for (int i = 0; i < x.Length; i++)          {              if (x[i] > xmax) xmax = x[i];              if (x[i] < xmin) xmin = x[i];              if (y[i] > ymax) ymax = y[i];              if (y[i] < ymin) ymin = y[i];          }      }        /// <summary>      ///      /// </summary>      public virtual void setPlotBounds()      {          findBounds();          //compute scaling factors          h = pic.Height;          w = pic.Width;          xfactor = 0.8F * w / (xmax - xmin);          xpmin = 0.05F * w;          xpmax = w - xpmin;            yfactor = 0.9F * h / (ymax - ymin);          ypmin = 0.05F * h;          ypmax = h - ypmin;          //create array of colors for bars          colors = new ArrayList();          colors.Add(new SolidBrush(Color.Red));          colors.Add(new SolidBrush(Color.Green));          colors.Add(new SolidBrush(Color.Blue));          colors.Add(new SolidBrush(Color.Magenta));          colors.Add(new SolidBrush(Color.Yellow));      }      /// <summary>      ///      /// </summary>      /// <param name="xp"></param>      /// <returns></returns>      public int calcx(float xp)      {          int ix = (int)((xp - xmin) * xfactor + xpmin);          return ix;      }      /// <summary>      ///      /// </summary>      /// <param name="yp"></param>      /// <returns></returns>      public int calcy(float yp)      {          yp = ((yp - ymin) * yfactor);          int iy = h - (int)(ypmax - yp);          return iy;      }        /// <summary>      ///      /// </summary>      public BarPlotForm()      {          InitializeComponent();          this.Text = "Bar Plot";      }      /// <summary>      ///      /// </summary>      /// <param name="container"></param>      public BarPlotForm(IContainer container)      {          container.Add(this);            InitializeComponent();      }        /// <summary>      ///      /// </summary>      /// <param name="sender"></param>      /// <param name="e"></param>      private void BarPlotForm_Load(object sender, EventArgs e)      {        }      /// <summary>      /// LinePlotForm需要重写此方法      ///      /// </summary>      /// <param name="sender"></param>      /// <param name="e"></param>     protected virtual void pic_Paint(object sender, PaintEventArgs e)      {                    Graphics g = e.Graphics;          if (hasData)          {              for (int i = 0; i < x.Length; i++)              {                  int ix = calcx(x[i]);                  int iy = calcy(y[i]);                  Brush br = (Brush)colors[i];                  g.FillRectangle(br, ix, h - iy, 20, iy);              }          }      }  }

　　

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/// <summary> /// Strategy Pattern 策略模式 ///20220918 /// geovindu,Geovin Du,涂聚文 /// </summary> public partial class LinePlotForm : BarPlotForm {     /// <summary>     ///     /// </summary>     public LinePlotForm()     {         init();         //InitializeComponent();     }     /// <summary>     ///     /// </summary>     protected void init()     {         bPen = new Pen(Color.Black);         this.Text = "Line Plot";               }     /// <summary>     /// 重写BarPlotForm的方法     /// </summary>     /// <param name="sender"></param>     /// <param name="e"></param>     protected override void pic_Paint(object sender, PaintEventArgs e)     {                   Graphics g = e.Graphics;         if (hasData)         {             for (int i = 1; i < x.Length; i++)             {                 int ix = calcx(x[i - 1]);                 int iy = calcy(y[i - 1]);                 int ix1 = calcx(x[i]);                 int iy1 = calcy(y[i]);                 g.DrawLine(bPen, ix, iy, ix1, iy1);             }         }     }     /// <summary>     ///     /// </summary>     private void InitializeComponent()     {         this.SuspendLayout();         //         // LinePlotForm         //         this.AutoScaleDimensions = new System.Drawing.SizeF(9F, 18F);         this.ClientSize = new System.Drawing.Size(678, 702);         this.Name = "LinePlotForm";         this.Load += new System.EventHandler(this.LinePlotForm_Load);         //this.Paint += new System.Windows.Forms.PaintEventHandler(this.LinePlotForm_Paint);                            this.ResumeLayout(false);       }     /// <summary>     ///     /// </summary>     /// <param name="sender"></param>     /// <param name="e"></param>     private void LinePlotForm_Load(object sender, EventArgs e)     {               }     /// <summary>     /// 在窗体画     /// </summary>     /// <param name="sender"></param>     /// <param name="e"></param>     private void LinePlotForm_Paint(object sender, PaintEventArgs e)     {         Graphics g = e.Graphics;         if (hasData)         {             for (int i = 1; i < x.Length; i++)             {                 int ix = calcx(x[i - 1]);                 int iy = calcy(y[i - 1]);                 int ix1 = calcx(x[i]);                 int iy1 = calcy(y[i]);                 g.DrawLine(bPen, ix, iy, ix1, iy1);             }         }     } }

　　

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/// <summary>  /// Strategy Pattern 策略模式  ///20220918  /// geovindu,Geovin Du,涂聚文  /// </summary>  public partial class StrategyPatternForm : Form  {        private void init()      {          EventHandler evh = new EventHandler(ButtonClick);          btLine.Click += evh;          btBar.Click += evh;          Context contxt = new Context();          btBar.setContext(contxt);          btLine.setContext(contxt);      }      /// <summary>      ///      /// </summary>      public StrategyPatternForm()      {          InitializeComponent();          init();      }      /// <summary>      ///      /// </summary>      /// <param name="sender"></param>      /// <param name="e"></param>      private void StrategyPatternForm_Load(object sender, EventArgs e)      {        }      /// <summary>      ///      /// </summary>      /// <param name="sender"></param>      /// <param name="e"></param>      private void ButtonClick(object sender, System.EventArgs e)      {          Command comd = (Command)sender;          comd.Execute();      }    }

　　

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