We help IT Professionals succeed at work.

We've partnered with Certified Experts, Carl Webster and Richard Faulkner, to bring you two Citrix podcasts. Learn about 2020 trends and get answers to your biggest Citrix questions!Listen Now

x

Cropping an image

noulouk
noulouk asked
on
Medium Priority
428 Views
Last Modified: 2008-01-16
Hi Experts,

Here is my custom control:

/* Title:
 * PictureBox with zoom and scroll functionallity
 */

#region Usings

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

#endregion

namespace PictureBoxCtrl
{
      /// <summary>
      /// Summary for the PictureBox Ctrl
      /// </summary>
      public class PictureBox : System.Windows.Forms.UserControl
      {
            #region Members

            public System.Windows.Forms.PictureBox PicBox;
            private System.Windows.Forms.Panel OuterPanel;
            private System.ComponentModel.Container components = null;
            private string m_sPicName = "";

        private bool down;
        private Point start;
        private Rectangle selection = Rectangle.Empty;

            #endregion

            #region Constants

            private double ZOOMFACTOR = 1.25;      // = 25% smaller or larger
            private int MINMAX = 5;                        // 5 times bigger or smaller than the ctrl

            #endregion

            #region Designer generated code

            private void InitializeComponent()
            {
                  this.PicBox = new System.Windows.Forms.PictureBox();
                  this.OuterPanel = new System.Windows.Forms.Panel();
                  this.OuterPanel.SuspendLayout();
                  this.SuspendLayout();
                  //
                  // PicBox
                  //
                  this.PicBox.Location = new System.Drawing.Point(0, 0);
                  this.PicBox.Name = "PicBox";
                  this.PicBox.Size = new System.Drawing.Size(150, 140);
                  this.PicBox.TabIndex = 3;
                  this.PicBox.TabStop = false;
                  //
                  // OuterPanel
                  //
                  this.OuterPanel.AutoScroll = true;
                  this.OuterPanel.BorderStyle = System.Windows.Forms.BorderStyle.FixedSingle;
                  this.OuterPanel.Controls.Add(this.PicBox);
                  this.OuterPanel.Dock = System.Windows.Forms.DockStyle.Fill;
                  this.OuterPanel.Location = new System.Drawing.Point(0, 0);
                  this.OuterPanel.Name = "OuterPanel";
                  this.OuterPanel.Size = new System.Drawing.Size(210, 190);
                  this.OuterPanel.TabIndex = 4;
                  //
                  // PictureBox
                  //
                  this.Controls.Add(this.OuterPanel);
                  this.Name = "PictureBox";
                  this.Size = new System.Drawing.Size(210, 190);
                  this.OuterPanel.ResumeLayout(false);
                  this.ResumeLayout(false);

            }
            #endregion

            #region Constructors

            public PictureBox()
            {
                  InitializeComponent ();
                  InitCtrl ();      // my special settings for the ctrl
            }

            #endregion

            #region Properties

            /// <summary>
            /// Property to select the picture which is displayed in the picturebox. If the
            /// file doesn´t exist or we receive an exception, the picturebox displays
            /// a red cross.
            /// </summary>
            /// <value>Complete filename of the picture, including path information</value>
            /// <remarks>Supported fileformat: *.gif, *.tif, *.jpg, *.bmp</remarks>
            [ Browsable ( false ) ]
            public string Picture
            {
                  get { return m_sPicName; }
                  set
                  {
                        if ( null != value )
                        {
                              if ( System.IO.File.Exists ( value ) )
                              {
                                    try
                                    {
                                          PicBox.Image = Image.FromFile ( value );
                                          m_sPicName = value;
                                    }
                                    catch ( OutOfMemoryException ex )
                                    {
                                          RedCross ();
                                    }
                              }
                              else
                              {                        
                                    RedCross ();
                              }
                        }
                  }
            }

            /// <summary>
            /// Set the frametype of the picturbox
            /// </summary>
            [ Browsable ( false ) ]
            public BorderStyle Border
            {
                  get { return OuterPanel.BorderStyle; }
                  set { OuterPanel.BorderStyle = value; }
            }

        public Rectangle Selection
        {
            get { return selection; }
        }
      

            #endregion

            #region Other Methods

            /// <summary>
            /// Special settings for the picturebox ctrl
            /// </summary>
            private void InitCtrl ()
            {
                  PicBox.SizeMode = PictureBoxSizeMode.StretchImage;
            PicBox.Location = new Point ( 0, 0 );
            PicBox.SizeMode = PictureBoxSizeMode.AutoSize;
                  OuterPanel.Dock = DockStyle.Fill;
                  //OuterPanel.Cursor = System.Windows.Forms.Cursors.NoMove2D;
                  OuterPanel.AutoScroll = true;
                  OuterPanel.MouseEnter += new EventHandler(PicBox_MouseEnter);
                  PicBox.MouseEnter += new EventHandler(PicBox_MouseEnter);
                  OuterPanel.MouseWheel += new MouseEventHandler(PicBox_MouseWheel);
            PicBox.MouseDown += new MouseEventHandler(PicBox_MouseDown);
            PicBox.MouseMove += new MouseEventHandler(PicBox_MouseMove);
            PicBox.MouseUp += new MouseEventHandler(PicBox_MouseUp);
            }

        void PicBox_MouseDown(object sender, MouseEventArgs e)
        {
            if (e.Button == MouseButtons.Left)
            {
                WindowsApplicationPlayer.NativeWIN32.InvalidateRect(IntPtr.Zero, IntPtr.Zero, true);
                //ControlPaint.DrawReversibleFrame(selection, this.BackColor, FrameStyle.Dashed);
                down = true;
                selection = Rectangle.Empty;
                ControlPaint.DrawReversibleFrame(selection, this.BackColor, FrameStyle.Dashed);
                start = this.PointToScreen(new Point(e.X + OuterPanel.AutoScrollPosition.X, e.Y + OuterPanel.AutoScrollPosition.Y));
            }
        }

        void PicBox_MouseMove(object sender, MouseEventArgs e)
        {
            if (down)
            {
                ControlPaint.DrawReversibleFrame(selection, this.BackColor, FrameStyle.Dashed);

                Point end = this.PointToScreen(new Point(e.X + OuterPanel.AutoScrollPosition.X, e.Y + OuterPanel.AutoScrollPosition.Y));  // or "-", I don't remember exactly
                selection = new Rectangle(start.X, start.Y, end.X - start.X, end.Y - start.Y);

                ControlPaint.DrawReversibleFrame(selection, this.BackColor, FrameStyle.Dashed);
            }

        }

        void PicBox_MouseUp(object sender, MouseEventArgs e)
        {
            if (down)
            {
                //ControlPaint.DrawReversibleFrame(selection, this.BackColor, FrameStyle.Dashed);
                down = false;
            }
        }
            /// <summary>
            /// Create a simple red cross as a bitmap and display it in the picturebox
            /// </summary>
            private void RedCross ()
            {
                  Bitmap bmp = new Bitmap ( OuterPanel.Width, OuterPanel.Height, System.Drawing.Imaging.PixelFormat.Format16bppRgb555 );
                  Graphics gr;
                  gr = Graphics.FromImage ( bmp );
                  Pen pencil = new Pen ( Color.Red, 5 );
                  gr.DrawLine ( pencil, 0, 0, OuterPanel.Width, OuterPanel.Height );
                  gr.DrawLine ( pencil, 0, OuterPanel.Height, OuterPanel.Width, 0  );
                  PicBox.Image = bmp;
                  gr.Dispose ();
            }

            #endregion

            #region Zooming Methods

            /// <summary>
            /// Make the PictureBox dimensions larger to effect the Zoom.
            /// </summary>
            /// <remarks>Maximum 5 times bigger</remarks>
            private void ZoomIn()
            {
            if ( ( PicBox.Width < ( MINMAX * OuterPanel.Width ) ) &&
                        ( PicBox.Height < ( MINMAX * OuterPanel.Height ) ) )
                  {
                        PicBox.Width = Convert.ToInt32 ( PicBox.Width * ZOOMFACTOR );
                        PicBox.Height = Convert.ToInt32 ( PicBox.Height * ZOOMFACTOR );
                        PicBox.SizeMode = PictureBoxSizeMode.StretchImage;
                  }
            }

            /// <summary>
            /// Make the PictureBox dimensions smaller to effect the Zoom.
            /// </summary>
            /// <remarks>Minimum 5 times smaller</remarks>
            private void ZoomOut()
            {
            if ( ( PicBox.Width > ( OuterPanel.Width / MINMAX ) ) &&
                        ( PicBox.Height > ( OuterPanel.Height / MINMAX ) ) )
                  {
                        PicBox.SizeMode = PictureBoxSizeMode.StretchImage;
                        PicBox.Width = Convert.ToInt32 ( PicBox.Width / ZOOMFACTOR );
                        PicBox.Height = Convert.ToInt32 ( PicBox.Height / ZOOMFACTOR );
                  }            
            }

            #endregion

            #region Mouse events

            /// <summary>
            /// We use the mousewheel to zoom the picture in or out
            /// </summary>
            /// <param name="sender"></param>
            /// <param name="e"></param>
            private void PicBox_MouseWheel(object sender, MouseEventArgs e)
            {
            //ControlPaint.DrawReversibleFrame(selection, this.BackColor, FrameStyle.Dashed);
            //if ( e.Delta < 0 )
            //{
            //    ZoomIn ();
            //}
            //else
            //{
            //    ZoomOut ();
            //}
            }

            /// <summary>
            /// Make sure that the PicBox have the focus, otherwise it doesn´t receive
            /// mousewheel events !.
            /// </summary>
            /// <param name="sender"></param>
            /// <param name="e"></param>
            private void PicBox_MouseEnter(object sender, EventArgs e)
            {
                  if ( PicBox.Focused == false )
                  {
                        PicBox.Focus ();
                  }
            }

            #endregion

            #region Disposing

            /// <summary>
            ///
            /// </summary>
            protected override void Dispose( bool disposing )
            {
                  if( disposing )
                  {
                        if( components != null )
                              components.Dispose();
                  }
                  base.Dispose( disposing );
            }

            #endregion
      }
}

I need to get the image of the area selected.

I try something like this but it doesn't work:

Graphics graphics = Graphics.FromImage(pictureBox1.PicBox.Image);
            Bitmap b = new Bitmap(pictureBox1.Selection.Width, pictureBox1.Selection.Height);
            graphics.DrawImage(b,new Rectangle(0,0, pictureBox1.Selection.Width,pictureBox1.Selection.Height), pictureBox1.Selection.Location.X, pictureBox1.Selection.Location.Y, pictureBox1.Selection.Width, pictureBox1.Selection.Height, GraphicsUnit.Pixel);
            pictureBox2.PicBox.Image =b;

Thanks in advance for your help.
Comment
Watch Question

Commented:
Bitmap b = new Bitmap(pictureBox1.Selection.Width, pictureBox1.Selection.Height);
Graphics graphics = Graphics.FromImage(b);
graphics.DrawImage(pictureBox1.PicBox.Image, <other parameters>);
graphics.Dispose();
pictureBox2.PicBox.Image =b;

I didn't test <other parameters>, only fixed bitmap and graphics handling.

Not the solution you were looking for? Getting a personalized solution is easy.

Ask the Experts

Author

Commented:
That works :-)
Thanks again.
Access more of Experts Exchange with a free account
Thanks for using Experts Exchange.

Create a free account to continue.

Limited access with a free account allows you to:

  • View three pieces of content (articles, solutions, posts, and videos)
  • Ask the experts questions (counted toward content limit)
  • Customize your dashboard and profile

*This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.

OR

Please enter a first name

Please enter a last name

8+ characters (letters, numbers, and a symbol)

By clicking, you agree to the Terms of Use and Privacy Policy.