public Bitmap LoadImageFromExtractIcon(string filename)
{
if (!System.IO.Directory.Exists(filename) && !System.IO.File.Exists(filename))
{
return(null);
}
Bitmap bm1 = null;
IntPtr hbitmap = IntPtr.Zero;
IShellFolder desktop = null;
IntPtr pidlParent = IntPtr.Zero;
IShellFolder shellFolder = null;
IUnknown iunk = null;
IExtractIcon extractIcon = null;
try
{
Debug.Write("Trying IExtractIcon\r\n");
Shell32.SHGetDesktopFolder(ref desktop);
int cParsed = 0;
int pdwAttrib = 0;
string filePath = filename;
if (System.IO.File.Exists(filename))
{
filePath = System.IO.Path.GetDirectoryName(filename);
}
desktop.ParseDisplayName(IntPtr.Zero, IntPtr.Zero, filePath, out cParsed, out pidlParent, out pdwAttrib);
Guid uuidShellFolder = new Guid("000214E6-0000-0000-C000-000000000046");
desktop.BindToObject(pidlParent, IntPtr.Zero, ref uuidShellFolder, out shellFolder);
Guid uuidExtractIcon = new Guid("000214eb-0000-0000-c000-000000000046");
iunk = GetUIObject(shellFolder, filename, uuidExtractIcon);
if (iunk == null)
{
Debug.Write(" IExtractIcon not supported\r\n");
return(null);
}
int hres = 0;
extractIcon = (IExtractIcon)iunk;
StringBuilder location = new StringBuilder(260, 260);
int iconIndex = 0;
GILFLAGS2 flags = GILFLAGS2.GIL_None;
hres = extractIcon.GetIconLocation(0, location, location.Capacity, out iconIndex, out flags);
IntPtr iconLarge = IntPtr.Zero;
IntPtr iconSmall = IntPtr.Zero;
uint iconSize = (16 | (48 << 16));
hres = extractIcon.Extract(location, iconIndex, out iconLarge, out iconSmall, iconSize);
Icon ico = Icon.FromHandle(iconLarge);
bm1 = ico.ToBitmap();
}
catch (Exception e)
{
Debug.Write(" Exception extracting image from IExtractIcon: " + e.Message + "\r\n");
}
finally
{
if (extractIcon != null)
{
Marshal.ReleaseComObject(extractIcon);
extractIcon = null;
}
if (iunk != null)
{
Marshal.ReleaseComObject(iunk);
iunk = null;
}
if (shellFolder != null)
{
Marshal.ReleaseComObject(shellFolder);
shellFolder = null;
}
if (pidlParent != IntPtr.Zero)
{
Allocator.Free(pidlParent);
pidlParent = IntPtr.Zero;
}
if (desktop != null)
{
Marshal.ReleaseComObject(desktop);
desktop = null;
}
if (_allocator != null)
{
Marshal.ReleaseComObject(_allocator);
_allocator = null;
}
}
return(bm1);
}
//==========================================================
//renvoie la miniature (ou à défaut l'icône) du fichier szFileName
//=========================================================
//IN szFileName : nom du fichier dont on veut la miniature
//IN dwCX : largeur de la miniature
//IN dwCY : hauteur de la miniature
//IN allowIcon: some videos don't have a true thumbnail.
// if true, it will return the icon of the default program used to open this kind of file
// (the icon of VLC for example)
//renvoie une instance d'image VB IPictureDisp
//==========================================================
private Bitmap ExtractImage(string szFileName, int dwCX, int dwCY, bool allowIcon = true)
{
int priority = 0;
int requestedColourDepth;
int flags;
SIZE sz;
IntPtr pidl = IntPtr.Zero;
IShellFolder isf = null;
IExtractImage ie = null;
IExtractIcon ii = null;
StringBuilder szPath;
int pindex = 0;
IntPtr pIconLarge = IntPtr.Zero;
IntPtr pIconSmall = IntPtr.Zero;
SHFILEINFO shgfi = new SHFILEINFO();
Bitmap ret = null;
requestedColourDepth = 32;
flags = (int)(EIEIFLAG.IEIFLAG_ASPECT | EIEIFLAG.IEIFLAG_OFFLINE | EIEIFLAG.IEIFLAG_SCREEN);
//on récupère le nom de fichier sous forme ITEMLIST (pidl) et le dossier parent sous forme IShellFolder
isf = GetShellFolder(szFileName, ref pidl);
// Try to get the thumbnail
ie = getThumbnail(isf, pidl);
// If not possible
if (ie == null)
{
// The icon
ii = getIcon(isf, pidl);
// If possible
if (!(ii == null))
{
// Extract the icon
szPath = new StringBuilder(260);
ii.GetIconLocation(0, szPath, 260, ref pindex, ref flags);
ii.Extract(szPath.ToString(), pindex, ref pIconLarge, ref pIconSmall, dwCX + 65536 * dwCX);
if (pIconLarge == IntPtr.Zero)
{
SHGetFileInfo(szFileName, 0, ref shgfi, Marshal.SizeOf(shgfi), SHGFIFLAGS.SHGFI_LARGEICON | SHGFIFLAGS.SHGFI_ICON | SHGFIFLAGS.SHGFI_OVERLAYINDEX);
ret = Icon.FromHandle(shgfi.hIcon).ToBitmap();
}
else
{
ret = Icon.FromHandle(pIconLarge).ToBitmap();
}
}
else
{
SHGetFileInfo(szFileName, 0, ref shgfi, Marshal.SizeOf(shgfi), SHGFIFLAGS.SHGFI_LARGEICON | SHGFIFLAGS.SHGFI_ICON | SHGFIFLAGS.SHGFI_OVERLAYINDEX);
ret = Icon.FromHandle(shgfi.hIcon).ToBitmap();
}
}
else // If possible
// Extract the thumbnail with the wanted dimensions
{
sz.cx = dwCX;
sz.cy = dwCY;
szPath = new StringBuilder(260);
EIEIFLAG f = (EIEIFLAG)flags;
int r = ie.GetLocation(szPath, szPath.Capacity, out priority, ref sz, requestedColourDepth, ref f);
try {
pIconLarge = ie.Extract();
} catch { }
// If not possible
if (pIconLarge == IntPtr.Zero)
{
// Retry to get the icon
ii = getIcon(isf, pidl);
// If possible
if (!(ii == null))
{
szPath = new StringBuilder(260);
ii.GetIconLocation(0, szPath, 260, ref pindex, ref flags);
ii.Extract(szPath.ToString(), pindex, ref pIconLarge, ref pIconSmall, dwCX + 65536 * dwCX);
if (pIconLarge == IntPtr.Zero)
{
SHGetFileInfo(szFileName, 0, ref shgfi, Marshal.SizeOf(shgfi), SHGFIFLAGS.SHGFI_LARGEICON | SHGFIFLAGS.SHGFI_ICON);
ret = Icon.FromHandle(shgfi.hIcon).ToBitmap();
}
else
{
if (!allowIcon)
{
return(null);
}
ret = Icon.FromHandle(pIconLarge).ToBitmap();
}
}
else
{
SHGetFileInfo(szFileName, 0, ref shgfi, Marshal.SizeOf(shgfi), SHGFIFLAGS.SHGFI_LARGEICON | SHGFIFLAGS.SHGFI_ICON);
ret = Icon.FromHandle(shgfi.hIcon).ToBitmap();
}
}
else
{
ret = (Bitmap)Bitmap.FromHbitmap(pIconLarge);
}
}
ILFree(pidl);
if (ret == null)
{
ret.MakeTransparent();
}
if (pIconLarge != IntPtr.Zero)
{
DeleteObject(pIconLarge);
}
if (pIconSmall != IntPtr.Zero)
{
DeleteObject(pIconSmall);
}
if (isf != null)
{
Marshal.ReleaseComObject(isf);
}
if (ie != null)
{
Marshal.ReleaseComObject(ie);
}
if (ii != null)
{
Marshal.ReleaseComObject(ii);
}
return(ret);
}