Region.Union : Region « System.Drawing « C# / C Sharp by API






Region.Union

 
  using System;
  using System.Drawing;
  using System.Drawing.Drawing2D;
  using System.Collections;
  using System.ComponentModel;
  using System.Windows.Forms;
  using System.Data;
  using System.Drawing.Imaging;

  public class Form1 : System.Windows.Forms.Form
  {
    public Form1()
    {
      InitializeComponent();
    }
    private void InitializeComponent()
    {
      this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
      this.ClientSize = new System.Drawing.Size(292, 273);
      this.Text = "";
      this.Resize += new System.EventHandler(this.Form1_Resize);
      this.Paint += new System.Windows.Forms.PaintEventHandler(this.Form1_Paint);

    }
    static void Main() 
    {
      Application.Run(new Form1());
    }

    private void Form1_Paint(object sender, System.Windows.Forms.PaintEventArgs e)
    {      
      Graphics g = e.Graphics;
      g.FillRectangle(Brushes.White, this.ClientRectangle);

      Region reg = new Region();
      reg.MakeEmpty();

      GraphicsPath gp = new GraphicsPath();
      gp.AddEllipse(10, 10, 50, 50);
      reg.Union(gp);

      gp.Reset();
      gp.AddLine(40, 40, 70, 10);
      gp.AddLine(70, 10, 140, 140);
      gp.CloseFigure();
      reg.Union(gp);

      reg.Union(new Rectangle(40, 50, 60, 60));

      // Set the clipping region
      g.SetClip(reg, CombineMode.Replace);

      g.FillRectangle(Brushes.Green, this.ClientRectangle);

      gp.Dispose();
      reg.Dispose();
    }

    private void Form1_Resize(object sender, System.EventArgs e)
    {
      Invalidate();
    }
  }

   
  








Related examples in the same category

1.new Region(GraphicsPath gp)
2.Region.Exclude
3.Region.IsEmpty
4.Region.IsInfinite
5.Region.IsVisible