Das funktioniert für mich in meinen Projekten, hoffe das hilft jemandem.
Es ist C# mit P/Invokes es wird bisher auf x86/x64-Systemen seit WinXP arbeiten.
(Shell.cs)
using System;
using System.Drawing;
using System.IO;
using System.Runtime.InteropServices;
namespace IconExtraction
{
internal sealed class Shell : NativeMethods
{
#region OfExtension
///<summary>
/// Get the icon of an extension
///</summary>
///<param name="filename">filename</param>
///<param name="overlay">bool symlink overlay</param>
///<returns>Icon</returns>
public static Icon OfExtension(string filename, bool overlay = false)
{
string filepath;
string[] extension = filename.Split('.');
string dirpath = Path.Combine(System.AppDomain.CurrentDomain.BaseDirectory, "cache");
Directory.CreateDirectory(dirpath);
if (String.IsNullOrEmpty(filename) || extension.Length == 1)
{
filepath = Path.Combine(dirpath, "dummy_file");
}
else
{
filepath = Path.Combine(dirpath, String.Join(".", "dummy", extension[extension.Length - 1]));
}
if (File.Exists(filepath) == false)
{
File.Create(filepath);
}
Icon icon = OfPath(filepath, true, true, overlay);
return icon;
}
#endregion
#region OfFolder
///<summary>
/// Get the icon of an extension
///</summary>
///<returns>Icon</returns>
///<param name="overlay">bool symlink overlay</param>
public static Icon OfFolder(bool overlay = false)
{
string dirpath = Path.Combine(System.AppDomain.CurrentDomain.BaseDirectory, "cache", "dummy");
Directory.CreateDirectory(dirpath);
Icon icon = OfPath(dirpath, true, true, overlay);
return icon;
}
#endregion
#region OfPath
///<summary>
/// Get the normal,small assigned icon of the given path
///</summary>
///<param name="filepath">physical path</param>
///<param name="small">bool small icon</param>
///<param name="checkdisk">bool fileicon</param>
///<param name="overlay">bool symlink overlay</param>
///<returns>Icon</returns>
public static Icon OfPath(string filepath, bool small = true, bool checkdisk = true, bool overlay = false)
{
Icon clone;
SHGFI_Flag flags;
SHFILEINFO shinfo = new SHFILEINFO();
if (small)
{
flags = SHGFI_Flag.SHGFI_ICON | SHGFI_Flag.SHGFI_SMALLICON;
}
else
{
flags = SHGFI_Flag.SHGFI_ICON | SHGFI_Flag.SHGFI_LARGEICON;
}
if (checkdisk == false)
{
flags |= SHGFI_Flag.SHGFI_USEFILEATTRIBUTES;
}
if (overlay)
{
flags |= SHGFI_Flag.SHGFI_LINKOVERLAY;
}
if (SHGetFileInfo(filepath, 0, ref shinfo, Marshal.SizeOf(shinfo), flags) == 0)
{
throw (new FileNotFoundException());
}
Icon tmp = Icon.FromHandle(shinfo.hIcon);
clone = (Icon)tmp.Clone();
tmp.Dispose();
if (DestroyIcon(shinfo.hIcon) != 0)
{
return clone;
}
return clone;
}
#endregion
}
}
(NativeMethods.cs)
using System;
using System.Drawing;
using System.Runtime.InteropServices;
namespace IconExtraction
{
internal class NativeMethods
{
public struct SHFILEINFO
{
public IntPtr hIcon;
public int iIcon;
public uint dwAttributes;
[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 260)]
public string szDisplayName;
[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 80)]
public string szTypeName;
};
[DllImport("user32.dll")]
public static extern int DestroyIcon(IntPtr hIcon);
[DllImport("shell32.dll", CharSet = CharSet.Auto, BestFitMapping = false, ThrowOnUnmappableChar = true)]
public static extern IntPtr ExtractIcon(IntPtr hInst, string lpszExeFileName, int nIconIndex);
[DllImport("Shell32.dll", BestFitMapping = false, ThrowOnUnmappableChar = true)]
public static extern int SHGetFileInfo(string pszPath, int dwFileAttributes, ref SHFILEINFO psfi, int cbFileInfo, SHGFI_Flag uFlags);
[DllImport("Shell32.dll")]
public static extern int SHGetFileInfo(IntPtr pszPath, uint dwFileAttributes, ref SHFILEINFO psfi, int cbFileInfo, SHGFI_Flag uFlags);
}
public enum SHGFI_Flag : uint
{
SHGFI_ATTR_SPECIFIED = 0x000020000,
SHGFI_OPENICON = 0x000000002,
SHGFI_USEFILEATTRIBUTES = 0x000000010,
SHGFI_ADDOVERLAYS = 0x000000020,
SHGFI_DISPLAYNAME = 0x000000200,
SHGFI_EXETYPE = 0x000002000,
SHGFI_ICON = 0x000000100,
SHGFI_ICONLOCATION = 0x000001000,
SHGFI_LARGEICON = 0x000000000,
SHGFI_SMALLICON = 0x000000001,
SHGFI_SHELLICONSIZE = 0x000000004,
SHGFI_LINKOVERLAY = 0x000008000,
SHGFI_SYSICONINDEX = 0x000004000,
SHGFI_TYPENAME = 0x000000400
}
}
Das ist für .exes in Ordnung, .dlls oder andere Dateien, die Symbole enthalten. Aber was ist mit Textdateien oder anderen einfachen Dateien, bei denen das Symbol je nach installiertem Programm oder einer vom Benutzer geänderten Einstellung variieren kann? –
Es sollte für ALLE Dateien funktionieren, die ein zugehöriges Icon haben, es muss kein assoziiertes Programm haben, was ich weiß. – Stefan
Was wird zurückgegeben, wenn kein Symbol zugeordnet ist? –