public void Dispose()
{
if (_disposed)
{
return;
}
if (_alloc != null)
{
Marshal.ReleaseComObject(_alloc);
}
_alloc = null;
if (ThumbNail != null)
{
ThumbNail.Dispose();
}
_disposed = true;
}
public Bitmap GetThumbnail(string fileName)
{
if (!File.Exists(fileName) && !Directory.Exists(fileName))
{
throw new FileNotFoundException(string.Format("The file '{0}' does not exist", fileName), fileName);
}
if (ThumbNail != null)
{
ThumbNail.Dispose();
ThumbNail = null;
}
var folder = getDesktopFolder;
if (folder == null)
{
return(ThumbNail);
}
var pidlMain = IntPtr.Zero;
try
{
var cParsed = 0;
var pdwAttrib = 0;
var filePath = Path.GetDirectoryName(fileName);
folder.ParseDisplayName(IntPtr.Zero, IntPtr.Zero, filePath, ref cParsed, ref pidlMain, ref pdwAttrib);
}
catch (Exception)
{
freeResources(pidlMain, folder, null, null);
throw;
}
if (pidlMain == IntPtr.Zero)
{
freeResources(pidlMain, folder, null, null);
return(null);
}
var iidShellFolder = new Guid("000214E6-0000-0000-C000-000000000046");
IShellFolder item = null;
try
{
folder.BindToObject(pidlMain, IntPtr.Zero, ref iidShellFolder, ref item);
}
catch (Exception)
{
freeResources(pidlMain, folder, null, item);
throw;
}
if (item == null)
{
freeResources(pidlMain, folder, null, null);
return(null);
}
IEnumIDList idEnum = null;
try
{
item.EnumObjects(IntPtr.Zero, (Eshcontf.ShcontfFolders | Eshcontf.ShcontfNonfolders), ref idEnum);
}
catch (Exception)
{
freeResources(pidlMain, folder, idEnum, item);
throw;
}
if (idEnum == null)
{
freeResources(pidlMain, folder, null, item);
return(null);
}
var pidl = IntPtr.Zero;
var fetched = 0;
var complete = false;
while (!complete)
{
var hRes = idEnum.Next(1, ref pidl, ref fetched);
if (hRes != 0)
{
pidl = IntPtr.Zero;
complete = true;
}
else
{
if (getThumbNail(fileName, pidl, item))
{
complete = true;
}
}
if (pidl != IntPtr.Zero)
{
allocator.Free(pidl);
}
}
freeResources(pidlMain, folder, idEnum, item);
return(ThumbNail);
}