• 2008-12-09
•   WinForms

I found this code somewhere on the web two years ago. It basically gets the large (32 x 32 pixels) and small (16 x 16 pixels) icons of an executable. The function returns an Icon object that can be displayed on a form’s icon area or used as a bitmap on a picture box or any other control that accepts bitmaps. For the code to work, create a windows application, drag a picture box control to the form area and leave it with its default name (PictureBox1).

using System;
using System.Drawing;
using System.Windows.Forms;
using System.Runtime.InteropServices;

namespace WindowsFormsApplication1
{
    public partial class Form3 : Form
    {
        public Form3()
        {
            InitializeComponent();
        }

        private void Form3_Load(object sender, EventArgs e)
        {
            //the path to an executable file, i chose windows media player
            string wmp = @"C:\Program Files\Windows Media Player\wmplayer.exe";

            //set the forms icon to the icon of the windows media player
            this.Icon = IconRipper.GetIcon(wmp, IconSize.Small);

            //display the larger icon (32 x 32) on the picturebox
            pictureBox1.Image = 
                IconRipper.GetIcon(wmp, IconSize.Large).ToBitmap();
        }
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct SHFILEINFO
    {
        public IntPtr hIcon;
        public int iIcon;
        public int dwAttributes;
        public string szDisplayName;
        public string szTypeName;
    }

    public enum IconSize
    {
        Large,  //32 x 32
        Small   //16 x 16
    }

    public class IconRipper
    {
        private const uint SHGFI_SYSICONINDEX = 0x4000;
        private const uint SHGFI_ICON = 0x100;
        private const uint SHGFI_LARGEICON = 0x0;
        private const uint SHGFI_SMALLICON = 0x1;

        [DllImport("Shell32.dll")]
        public static extern int SHGetFileInfo(string path, uint fileAttributes, 
            out SHFILEINFO psfi, uint fileInfo, uint flags);

        public static Icon GetIcon(string path, IconSize iconSize)
        {
            SHFILEINFO info = new SHFILEINFO();
            uint size = iconSize == IconSize.Large ? 
                SHGFI_LARGEICON : SHGFI_SMALLICON;

            uint flags = SHGFI_SYSICONINDEX | size | SHGFI_ICON;
            int hTcdf = SHGetFileInfo(path, 0, out info, 
                (uint)Marshal.SizeOf(typeof(SHFILEINFO)), flags);

            IntPtr handleIcon = info.hIcon;
            return Icon.FromHandle(handleIcon);
        }
    }
}