Get associated icon from file

public enum IconSize

{

    Small,

    Large

}

public class IconExtractor

{

    private const uint SHGFI_ICON = 0x100;

    private const uint SHGFI_LARGEICON = 0x0;

    private const uint SHGFI_SMALLICON = 0x1;

    [StructLayout(LayoutKind.Sequential)]

    private struct SHFILEINFO

    {

        public IntPtr hIcon;

        public IntPtr iIcon;

        public uint dwAttributes;

        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 260)]

        public string szDisplayName;

        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 80)]

        public string szTypeName;

    };

    [DllImport("shell32.dll")]

    private static extern IntPtr SHGetFileInfo(string pszPath, uint dwFileAttributes, ref SHFILEINFO psfi, uint cbSizeFileInfo, uint uFlags);

    public IconExtractor()

    {

    }

    public System.Drawing.Icon Extract(string File, IconSize Size)

    {

        IntPtr hIcon;

        SHFILEINFO shinfo = new SHFILEINFO();

        if (Size == IconSize.Large)

        {

            hIcon = SHGetFileInfo(File, 0, ref shinfo, (uint)Marshal.SizeOf(shinfo), SHGFI_ICON | SHGFI_LARGEICON);

        }

        else

        {

            hIcon = SHGetFileInfo(File, 0, ref shinfo, (uint)Marshal.SizeOf(shinfo), SHGFI_ICON | SHGFI_SMALLICON);

        }

        return System.Drawing.Icon.FromHandle(shinfo.hIcon);

    }

    public System.Drawing.Icon Extract(string File)

    {

        return this.Extract(File, IconSize.Small);

    }

}