One of my old open source project include an Icon class that does exactly that, feel free to rip it, seeing the age I put this file in the public domain anyway it's just PInvoke for most part.
To get an icon you use for example :
Icon zipIcon = BlackFox.Win32.Icons.IconFromExtension(".zip", SystemIconSize.Small);
Full sample :
using System;
using System.Windows.Forms;
using BlackFox.Win32;
using System.Drawing;
class Program
{
static void Main(string[] args)
{
PictureBox pict = new PictureBox();
pict.Image = Icons.IconFromExtension(".zip", Icons.SystemIconSize.Large).ToBitmap();
pict.Dock = DockStyle.Fill;
pict.SizeMode = PictureBoxSizeMode.CenterImage;
Form form = new Form();
form.Controls.Add(pict);
Application.Run(form);
}
}
The library :
using System;
using System.Drawing;
using System.Runtime.InteropServices;
using Microsoft.Win32;
using System.Reflection;
using System.Collections.Generic;
namespace BlackFox.Win32
{
public static class Icons
{
#region Custom exceptions class
public class IconNotFoundException : Exception
{
public IconNotFoundException(string fileName, int index)
: base(string.Format("Icon with Id = {0} wasn't found in file {1}", index, fileName))
{
}
}
public class UnableToExtractIconsException : Exception
{
public UnableToExtractIconsException(string fileName, int firstIconIndex, int iconCount)
: base(string.Format("Tryed to extract {2} icons starting from the one with id {1} from the "{0}" file but failed", fileName, firstIconIndex, iconCount))
{
}
}
#endregion
#region DllImports
/// <summary>
/// Contains information about a file object.
/// </summary>
struct SHFILEINFO
{
/// <summary>
/// Handle to the icon that represents the file. You are responsible for
/// destroying this handle with DestroyIcon when you no longer need it.
/// </summary>
public IntPtr hIcon;
/// <summary>
/// Index of the icon image within the system image list.
/// </summary>
public IntPtr iIcon;
/// <summary>
/// Array of values that indicates the attributes of the file object.
/// For information about these values, see the IShellFolder::GetAttributesOf
/// method.
/// </summary>
public uint dwAttributes;
/// <summary>
/// String that contains the name of the file as it appears in the Microsoft
/// Windows Shell, or the path and file name of the file that contains the
/// icon representing the file.
/// </summary>
[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 260)]
public string szDisplayName;
/// <summary>
/// String that describes the type of file.
/// </summary>
[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 80)]
public string szTypeName;
};
[Flags]
enum FileInfoFlags : int
{
/// <summary>
/// Retrieve the handle to the icon that represents the file and the index
/// of the icon within the system image list. The handle is copied to the
/// hIcon member of the structure specified by psfi, and the index is copied
/// to the iIcon member.
/// </summary>
SHGFI_ICON = 0x000000100,
/// <summary>
/// Indicates that the function should not attempt to access the file
/// specified by pszPath. Rather, it should act as if the file specified by
/// pszPath exists with the file attributes passed in dwFileAttributes.
/// </summary>
SHGFI_USEFILEATTRIBUTES = 0x000000010
}
/// <summary>
/// Creates an array of handles to large or small icons extracted from
/// the specified executable file, dynamic-link library (DLL), or icon
/// file.
/// </summary>
/// <param name="lpszFile">
/// Name of an executable file, DLL, or icon file from which icons will
/// be extracted.
/// </param>
/// <param name="nIconIndex">
/// <para>
/// Specifies the zero-based index of the first icon to extract. For
/// example, if this value is zero, the function extracts the first
/// icon in the specified file.
/// </para>
/// <para>
/// If this value is ?1 and <paramref name="phiconLarge"/> and
/// <paramref name="phiconSmall"/> are both NULL, the function returns
/// the total number of icons in the specified file. If the file is an
/// executable file or DLL, the return value is the number of
/// RT_GROUP_ICON resources. If the file is an .ico file, the return
/// value is 1.
/// </para>
/// <para>
/// Windows 95/98/Me, Windows NT 4.0 and later: If this value is a
/// negative number and either <paramref name="phiconLarge"/> or
/// <paramref name="phiconSmall"/> is not NULL, the function begins by
/// extracting the icon whose resource identifier is equal to the
/// absolute value of <paramref name="nIconIndex"/>. For example, use -3
/// to extract the icon whose resource identifier is 3.
/// </para>
/// </param>
/// <param name="phIconLarge">
/// An array of icon handles that receives handles to the large icons
/// extracted from the file. If this parameter is NULL, no large icons
/// are extracted from the file.
/// </param>
/// <param name="phIconSmall">
/// An array of icon handles that receives handles to the small icons
/// extracted from the file. If this parameter is NULL, no small icons
/// are extracted from the file.
/// </param>
/// <param name="nIcons">
/// Specifies the number of icons to extract from the file.
/// </param>
/// <returns>
/// If the <paramref name="nIconIndex"/> parameter is -1, the
/// <paramref name="phIconLarge"/> parameter is NULL, and the
/// <paramref name="phiconSmall"/> parameter is NULL, then the return
/// value is the number of icons contained in the specified file.
/// Otherwise, the return value is the number of icons successfully
/// extracted from the file.
/// </returns>
[DllImport("Shell32", CharSet = CharSet.Auto)]
extern static int ExtractIconEx(
[MarshalAs(UnmanagedType.LPTStr)]
string lpszFile,
int nIconIndex,
IntPtr[] phIconLarge,
IntPtr[] phIconSmall,
int nIcons);
[DllImport("Shell32", CharSet = CharSet.Auto)]
extern static IntPtr SHGetFileInfo(
string pszPath,
int dwFileAttributes,
out SHFILEINFO psfi,
int cbFileInfo,
FileInfoFlags uFlags);
#endregion
/// <summary>
/// Two constants extracted from the FileInfoFlags, the only that are
/// meaningfull for the user of this class.
/// </summary>
public enum SystemIconSize : int
{
Large = 0x000000000,
Small = 0x000000001
}
/// <summary>
/// Get the number of icons in the specified file.
/// </summary>
/// <param name="fileName">Full path of the file to look for.</param>
/// <returns></returns>
static int GetIconsCountInFile(string fileName)
{
return ExtractIconEx(fileName, -1, null, null, 0);
}
#region ExtractIcon-like functions
public static void ExtractEx(string fileName, List<Icon> largeIcons,
List<Icon> smallIcons, int firstIconIndex, int iconCount)
{
/*
* Memory allocations
*/
IntPtr[] smallIconsPtrs = null;
IntPtr[] largeIconsPtrs = null;
if (smallIcons != null)
{
smallIconsPtrs = new IntPtr[iconCount];
}
if (largeIcons != null)
{
largeIconsPtrs = new IntPtr[iconCount];
}
/*
* Call to native Win32 API
*/
int apiResult = ExtractIconEx(fileName, firstIconIndex, largeIconsPtrs, smallIconsPtrs, iconCount);
if (apiResult != iconCount)
{
throw new UnableToExtractIconsException(fileName, firstIconIndex, iconCount);
}
/*
* Fill lists
*/
if (smallIcons != null)
{
smallIcons.Clear();
foreach (IntPtr actualIconPtr in smallIconsPtrs)
{
smallIcons.Add(Icon.FromHandle(actualIconPtr));
}
}
if (largeIcons != null)
{
largeIcons.Clear();
foreach (IntPtr actualIconPtr in largeIconsPtrs)
{
largeIcons.Add(Icon.FromHandle(actualIconPtr));
}
}
}
public static List<Icon> ExtractEx(string fileName, SystemIconSize size,
int firstIconIndex, int iconCount)
{
List<Icon> iconList = new List<Icon>();
switch (size)
{
case SystemIconSize.Large:
ExtractEx(fileName, iconList, null, firstIconIndex, iconCount);
break;
case SystemIconSize.Small:
ExtractEx(fileName, null, iconList, firstIconIndex, iconCount);
break;
default:
throw new ArgumentOutOfRangeException("size");
}
return iconList;
}
public static void Extract(string fileName, List<Icon> largeIcons, List<Icon> smallIcons)
{
int iconCount = GetIconsCountInFile(fileName);
ExtractEx(fileName, largeIcons, smallIcons, 0, iconCount);
}
public static List<Icon> Extract(string fileName, SystemIconSize size)
{
int iconCount = GetIconsCountInFile(fileName);
return ExtractEx(fileName, size, 0, iconCount);
}
public static Icon ExtractOne(string fileName, int index, SystemIconSize size)
{
try
{
List<Icon> iconList = ExtractEx(
