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ImageList Class

Provides methods to manage a collection of Image objects. This class cannot be inherited.

Namespace:  System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

public sealed class ImageList : Component

ImageList is typically used by other controls, such as the ListView, TreeView, or ToolBar. You can add bitmaps or icons to the ImageList, and the other controls are able to use the images as they require.

ImageList uses a handle to manage the list of images. The Handle is not created until certain operations, such as getting the Handle or calling Draw, are performed on the image list. Performing other operations, such as setting the ColorDepth or ImageSize will cause the Handle to be recreated. Therefore, you should perform these operations before you add images to the ImageList. In addition, when you work with forms that will be localized, you should always add an ImageList and images when the Language property of a form is set to Default. Changing the form's language before you add images will corrupt the application resource files.

The following code example shows how to select, remove, and display images.

namespace myImageRotator
{
	using System;
	using System.Drawing;
	using System.ComponentModel;
	using System.Windows.Forms;

	public class Form1 : System.Windows.Forms.Form
	{
		private System.ComponentModel.IContainer components;
		private System.Windows.Forms.ListBox listBox1;
		private System.Windows.Forms.Label label3;
		private System.Windows.Forms.Button button1;
		private System.Windows.Forms.Button button2;
		private System.Windows.Forms.Button button3;
		private System.Windows.Forms.Button button4;
		private System.Windows.Forms.PictureBox pictureBox1;
		private System.Windows.Forms.ImageList imageList1;
		private System.Windows.Forms.OpenFileDialog openFileDialog1;
		protected Graphics myGraphics;
		private System.Windows.Forms.Panel panel1;
		private System.Windows.Forms.Label label5;
		private int currentImage = 0;

		public Form1()
		{
			InitializeComponent();
			imageList1 = new ImageList () ;

			// The default image size is 16 x 16, which sets up a larger 
			// image size. 
			imageList1.ImageSize = new Size(255,255);
			imageList1.TransparentColor = Color.White;

			// Assigns the graphics object to use in the draw options.
			myGraphics = Graphics.FromHwnd(panel1.Handle);
		}

        private void InitializeComponent()
        {
            this.components = new System.ComponentModel.Container();
            this.listBox1 = new System.Windows.Forms.ListBox();
            this.label3 = new System.Windows.Forms.Label();
            this.button1 = new System.Windows.Forms.Button();
            this.button2 = new System.Windows.Forms.Button();
            this.button3 = new System.Windows.Forms.Button();
            this.button4 = new System.Windows.Forms.Button();
            this.pictureBox1 = new System.Windows.Forms.PictureBox();
            this.imageList1 = new System.Windows.Forms.ImageList(this.components);
            this.openFileDialog1 = new System.Windows.Forms.OpenFileDialog();
            this.panel1 = new System.Windows.Forms.Panel();
            this.label5 = new System.Windows.Forms.Label();
            this.SuspendLayout();

            this.listBox1.Location = new System.Drawing.Point(16, 16);
            this.listBox1.Size = new System.Drawing.Size(400, 95);
            this.listBox1.TabIndex = 0;

            this.label3.Location = new System.Drawing.Point(24, 168);
            this.label3.Text = "label3";

            this.button1.Location = new System.Drawing.Point(96, 128);
            this.button1.Size = new System.Drawing.Size(104, 23);
            this.button1.Text = "Show Next Image";
            this.button1.Click += new System.EventHandler(this.button1_Click);

            this.button2.Location = new System.Drawing.Point(208, 128);
            this.button2.Size = new System.Drawing.Size(104, 23);
            this.button2.Text = "Remove Image";
            this.button2.Click += new System.EventHandler(this.button2_Click);

            this.button3.Location = new System.Drawing.Point(320, 128);
            this.button3.Text = "Clear List";
            this.button3.Click += new System.EventHandler(this.button3_Click);

            this.button4.Location = new System.Drawing.Point(16, 128);
            this.button4.Text = "Open Image";
            this.button4.Click += new System.EventHandler(this.button4_Click);

            this.pictureBox1.Location = new System.Drawing.Point(328, 232);
            this.pictureBox1.Size = new System.Drawing.Size(336, 192);

            this.imageList1.ImageSize = new System.Drawing.Size(16, 16);
            this.imageList1.TransparentColor = System.Drawing.Color.Transparent;

            this.panel1.Location = new System.Drawing.Point(8, 240);
            this.panel1.Size = new System.Drawing.Size(296, 184);

            this.label5.Location = new System.Drawing.Point(168, 168);
            this.label5.Size = new System.Drawing.Size(312, 40);
            this.label5.Text = "label5";

            this.ClientSize = new System.Drawing.Size(672, 461);
            this.Controls.Add(this.label5);
            this.Controls.Add(this.panel1);
            this.Controls.Add(this.pictureBox1);
            this.Controls.Add(this.button4);
            this.Controls.Add(this.button3);
            this.Controls.Add(this.button2);
            this.Controls.Add(this.button1);
            this.Controls.Add(this.label3);
            this.Controls.Add(this.listBox1);
            this.ResumeLayout(false);
        }

        // Display the image. 
        private void button1_Click (object sender, System.EventArgs e)
		{
			if(imageList1.Images.Empty != true)
			{
				if(imageList1.Images.Count-1 > currentImage)
				{
					currentImage++;
				}
				else
				{
					currentImage=0;
				}
				panel1.Refresh();

                // Draw the image in the panel.
				imageList1.Draw(myGraphics,10,10,currentImage);

                // Show the image in the PictureBox.
				pictureBox1.Image = imageList1.Images[currentImage];
				label3.Text = "Current image is " + currentImage ;
				listBox1.SelectedIndex = currentImage;
				label5.Text = "Image is " + listBox1.Text ;
            }
		}

        // Remove the image. 
		private void button2_Click (object sender, System.EventArgs e)
		{
			imageList1.Images.RemoveAt(listBox1.SelectedIndex);
			listBox1.Items.Remove(listBox1.SelectedItem);
		}

        // Clear all images. 
		private void button3_Click (object sender, System.EventArgs e)
		{
			imageList1.Images.Clear();
			listBox1.Items.Clear();
		}

        // Find an image. 
		private void button4_Click (object sender, System.EventArgs e)
		{
			openFileDialog1.Multiselect = true ;
			if(openFileDialog1.ShowDialog() == DialogResult.OK)
			{
				if (openFileDialog1.FileNames != null)
				{
					for(int i =0 ; i < openFileDialog1.FileNames.Length ; i++ )
					{
						addImage(openFileDialog1.FileNames[i]);
					}
				}
				else
					addImage(openFileDialog1.FileName);
			}

		}

		private void addImage(string imageToLoad)
		{
			if (imageToLoad != "")
			{
				imageList1.Images.Add(Image.FromFile(imageToLoad));
				listBox1.BeginUpdate();
				listBox1.Items.Add(imageToLoad);
				listBox1.EndUpdate();
			}
		}
        [STAThread]
        public static void Main(string[] args) 
		{
			Application.Run(new Form1());
		}
	}
}

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 3.5, 2.0, 1.0
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