Course IPCis: Image Processing with C# Chapter C1: The Complete Code of the Bitmap Project Copyright © by V. Miszalok, last update: 06-07-2008

Copy all this code into an empty Form1.cs of a new Windows Application C#-project bitmap1 and clear Form1.Designer.cs and Program.cs.

using System;
using System.Drawing;
using System.Drawing.Imaging;
using System.Windows.Forms;

public class Form1 : Form
{ [STAThread] static void Main() { Application.Run( new Form1() ); }
  Brush bbrush = SystemBrushes.ControlText;
  Brush rbrush = new SolidBrush( Color.Red );
  Bitmap bmp;
  int nClicks;

  public Form1()
  { MenuItem miRead = new MenuItem( "&Read", new EventHandler( MenuFileRead ) );
    MenuItem miExit = new MenuItem( "&Exit", new EventHandler( MenuFileExit ) );
    MenuItem miFile = new MenuItem( "&File", new MenuItem[] { miRead, miExit } );
    Menu = new System.Windows.Forms.MainMenu( new MenuItem[] { miFile } );
    Text = "Bitmap1";
    SetStyle( ControlStyles.ResizeRedraw, true );
    Width = 1024;
    Height = 800;
    try { //Delete this and the following 6 lines if you have no Internet connection running.
    System.Net.WebRequest  webreq = System.Net.WebRequest.Create( "http://www.miszalok.de/Images/Madonna.bmp" );
    System.Net.WebResponse webres = webreq.GetResponse();
    System.IO.Stream       stream = webres.GetResponseStream();
    bmp = (Bitmap)Image.FromStream( stream );
    Invalidate();
    } catch {};
  }

  private void MenuFileRead( object obj, EventArgs ea )
  { OpenFileDialog dlg = new OpenFileDialog();
    if ( dlg.ShowDialog() != DialogResult.OK ) return;
    try { bmp = (Bitmap)Image.FromFile( dlg.FileName ); } catch { return; }
    nClicks = 0;
    Invalidate();
  }

  private void MenuFileExit( object obj, EventArgs ea )
  { Application.Exit(); }

  protected override void OnMouseDown( MouseEventArgs e )
  { nClicks++;
    Invalidate();
  }

  protected override void OnPaint( PaintEventArgs e )
  { Graphics g = e. Graphics;
    if ( bmp == null ) { g.DrawString( "Open an Image File !", Font, bbrush, 0, 0 ); return; }
    Rectangle cr = ClientRectangle;
    int line = 0;
    switch ( nClicks % 9 )
    { case 0: //Information
        g.DrawString( "RawFormat = " + bmp.RawFormat.ToString(), Font, bbrush, 0, line+=Font.Height );
        if ( bmp.RawFormat.Guid == ImageFormat.Bmp.Guid )
          g.DrawString( "BMP", Font, bbrush, 0, line+=Font.Height );
        if ( bmp.RawFormat.Guid == ImageFormat.Jpeg.Guid )
          g.DrawString( "JPG", Font, bbrush, 0, line+=Font.Height );
        g.DrawString( "Width       = " + bmp.Width.ToString()      , Font, bbrush, 0, line+=Font.Height );
        g.DrawString( "Height      = " + bmp.Height.ToString()     , Font, bbrush, 0, line+=Font.Height );
        g.DrawString( "PixelFormat = " + bmp.PixelFormat.ToString(), Font, bbrush, 0, line+=Font.Height );
        g.DrawString( "Click on left mouse button !", Font, rbrush, 0, line+=Font.Height);
        break;
      case 1: //Raw display
        g.DrawImage( bmp, 0, Font.Height );
        g.DrawString( "Click on left mouse button !", Font, rbrush, 0, 0 );
        break;
      case 2: //Center
        Int32 x = (cr.Width  - bmp.Width ) / 2;
        Int32 y = (cr.Height - bmp.Height) / 2;
        g.DrawImage(bmp, x, y, bmp.Width, bmp.Height);
        g.DrawString( "Change window size ! Click on left mouse button !", Font, rbrush, 0, 0 );
        break;
      case 3: //Horizontal stretch
        x = 0;
        y = ( cr.Height - bmp.Height / 2 ) / 2;
        g.DrawImage( bmp, x, y, cr.Width, bmp.Height / 2 ); //full form width, half bmp height
        g.DrawString( "Change window size ! Click on left mouse button !", Font, rbrush, 0, 0 );
        break;
      case 4: //Vertical stretch
        x = ( cr.Width - bmp.Width / 2 ) / 2;
        y = 0;
        g.DrawImage( bmp, x, y, bmp.Width / 2, cr.Height ); //half bmp width, full form height
        g.DrawString( "Change window size ! Click on left mouse button !", Font, rbrush, 0, 0 );
        break;
      case 5: //Full size
        g.DrawImage( bmp, cr );
        g.DrawString( "Change window size ! Click on left mouse button !", Font, rbrush, 0, 0 );
        break;
      case 6: //Mirror
        g.DrawImage( bmp, cr.Width/2, cr.Height/2,  cr.Width/2,  cr.Height/2 );
        g.DrawImage( bmp, cr.Width/2, cr.Height/2, -cr.Width/2,  cr.Height/2 );
        g.DrawImage( bmp, cr.Width/2, cr.Height/2,  cr.Width/2, -cr.Height/2 );
        g.DrawImage( bmp, cr.Width/2, cr.Height/2, -cr.Width/2, -cr.Height/2 );
        g.DrawString( "Change window size ! Click on left mouse button !", Font, rbrush, 0, 0 );
        break;
      case 7: //Zoom animation
        x = cr.Width  / 20;
        y = cr.Height / 20;
        for ( Int32 i = 0; i < 20; i++ )
          g.DrawImage( bmp, 0, 0, cr.Width - x*i, cr.Height - y*i );
        g.DrawString( "Change window size ! Click on left mouse button !", Font, rbrush, 0, 0 );
        break;
      case 8: //Rotation animation
        Single fx = cr.Width  / 100;
        Single fy = cr.Height / 100;
        PointF[] p = new PointF[3];
        p[1].X = cr.Width;
        p[2].Y = cr.Height;
        do
        { p[0].X += fx;
          p[1].Y += fy;
          p[2].Y -= fy;
          g.DrawImage( bmp, p );
        } while ( p[2].Y > 0 );
        g.DrawString( "Change window size ! Click on left mouse button !", Font, rbrush, 0, 0 );
        break;
    }
  }
}