public void Dispose()
{
if (_disposed)
{
return;
}
if (_alloc != null)
{
Marshal.ReleaseComObject(_alloc);
}
_alloc = null;
if (ThumbNail != null)
{
ThumbNail.Dispose();
}
_disposed = true;
}
protected bool ReadImageResource(FileStream stream)
{
bool bSuccess = false;
BinaryReader binReader = new BinaryReader(stream);
try
{
int nLength = 0;
byte [] Length = binReader.ReadBytes(4);
m_ImageResource = new ImageResource();
m_ResolutionInfo = new ResolutionInfo();
m_DisplayInfo = new DisplayInfo();
m_ThumbNail = new ThumbNail();
if(SwapBytes(Length,4)) nLength = BitConverter.ToInt32(Length,0);
m_ImageResource.nLength = nLength;
int nBytesRead = 0;
int nTotalBytes = m_ImageResource.nLength;
long nStreamLen = stream.Length;
while(stream.Position < nStreamLen && nBytesRead < nTotalBytes)
{
m_ImageResource.Reset();
m_ImageResource.OSType = binReader.ReadBytes(4);
nBytesRead += 4;
ASCIIEncoding encoding = new ASCIIEncoding();
if(encoding.GetString(m_ImageResource.OSType).Equals("8BIM"))
{
byte [] ID = binReader.ReadBytes(2);
nBytesRead += 2;
if(SwapBytes(ID,2)) m_ImageResource.nID = BitConverter.ToInt16(ID,0);
byte SizeOfName = binReader.ReadByte();
nBytesRead += 1;
int nSizeOfName = (int)SizeOfName;
if(nSizeOfName>0)
{
if((nSizeOfName % 2)!=0) // must read 1 more byte to make size even
{
SizeOfName = binReader.ReadByte();
nBytesRead += 1;
}
m_ImageResource.Name = new byte[nSizeOfName];
m_ImageResource.Name = binReader.ReadBytes(nSizeOfName);
nBytesRead += nSizeOfName;
}
SizeOfName = binReader.ReadByte();
nBytesRead += 1;
byte [] Size = binReader.ReadBytes(4);
if(SwapBytes(Size,4)) m_ImageResource.nSize = BitConverter.ToInt32(Size,0);
nBytesRead += 4;
if((m_ImageResource.nSize % 2) != 0) // resource data must be even
m_ImageResource.nSize++;
if(m_ImageResource.nSize>0)
{
byte [] IntValue = new byte[4];
byte [] ShortValue = new byte[2];
switch(m_ImageResource.nID)
{
case 1005:
{
m_bResolutionInfoFilled = true;
ShortValue = binReader.ReadBytes(2);
if(SwapBytes(ShortValue,2)) m_ResolutionInfo.hRes = BitConverter.ToInt16(ShortValue,0);
nBytesRead += 2;
IntValue = binReader.ReadBytes(4);
if(SwapBytes(IntValue,4)) m_ResolutionInfo.hResUnit = BitConverter.ToInt32(IntValue,0);
nBytesRead += 4;
ShortValue = binReader.ReadBytes(2);
if(SwapBytes(ShortValue,2)) m_ResolutionInfo.widthUnit = BitConverter.ToInt16(ShortValue,0);
nBytesRead += 2;
ShortValue = binReader.ReadBytes(2);
if(SwapBytes(ShortValue,2)) m_ResolutionInfo.vRes = BitConverter.ToInt16(ShortValue,0);
nBytesRead += 2;
IntValue = binReader.ReadBytes(4);
if(SwapBytes(IntValue,4)) m_ResolutionInfo.vResUnit = BitConverter.ToInt32(IntValue,0);
nBytesRead += 4;
ShortValue = binReader.ReadBytes(2);
if(SwapBytes(ShortValue,2)) m_ResolutionInfo.heightUnit = BitConverter.ToInt16(ShortValue,0);
nBytesRead += 2;
}
break;
case 1007:
{
ShortValue = binReader.ReadBytes(2);
nBytesRead += 2;
if(SwapBytes(ShortValue,2)) m_DisplayInfo.ColourSpace = BitConverter.ToInt16(ShortValue,0);
for(int n=0; n<4; ++n)
{
ShortValue = binReader.ReadBytes(2);
nBytesRead += 2;
if(SwapBytes(ShortValue,2)) m_DisplayInfo.Colour[n] = BitConverter.ToInt16(ShortValue,0);
}
ShortValue = binReader.ReadBytes(2);
nBytesRead += 2;
if(SwapBytes(ShortValue,2)) m_DisplayInfo.Opacity = BitConverter.ToInt16(ShortValue,0);
if(m_DisplayInfo.Opacity<0 || m_DisplayInfo.Opacity>100) m_DisplayInfo.Opacity = 100;
byte c = binReader.ReadByte();
nBytesRead += 1;
if(c == 0x00) m_DisplayInfo.kind = false;
else m_DisplayInfo.kind = true;
nBytesRead += 1;
m_DisplayInfo.padding = binReader.ReadByte();
}
break;
case 1034:
{
ShortValue = binReader.ReadBytes(2);
nBytesRead += 2;
int nCopyright = 0;
if(SwapBytes(ShortValue,2)) nCopyright = BitConverter.ToInt16(ShortValue,0);
if(nCopyright>0) m_bCopyright = true;
else m_bCopyright = false;
}
break;
case 1033:
case 1036:
{
m_bThumbnailFilled = true;
IntValue = binReader.ReadBytes(4);
if(SwapBytes(IntValue,4)) m_ThumbNail.nFormat = BitConverter.ToInt32(IntValue,0);
nBytesRead += 4;
IntValue = binReader.ReadBytes(4);
if(SwapBytes(IntValue,4)) m_ThumbNail.nWidth = BitConverter.ToInt32(IntValue,0);
nBytesRead += 4;
IntValue = binReader.ReadBytes(4);
if(SwapBytes(IntValue,4)) m_ThumbNail.nHeight = BitConverter.ToInt32(IntValue,0);
nBytesRead += 4;
IntValue = binReader.ReadBytes(4);
if(SwapBytes(IntValue,4)) m_ThumbNail.nWidthBytes = BitConverter.ToInt32(IntValue,0);
nBytesRead += 4;
IntValue = binReader.ReadBytes(4);
if(SwapBytes(IntValue,4)) m_ThumbNail.nSize = BitConverter.ToInt32(IntValue,0);
nBytesRead += 4;
IntValue = binReader.ReadBytes(4);
if(SwapBytes(IntValue,4)) m_ThumbNail.nCompressedSize = BitConverter.ToInt32(IntValue,0);
nBytesRead += 4;
ShortValue = binReader.ReadBytes(2);
nBytesRead += 2;
if(SwapBytes(ShortValue,2)) m_ThumbNail.nBitPerPixel = BitConverter.ToInt16(ShortValue,0);
ShortValue = binReader.ReadBytes(2);
nBytesRead += 2;
if(SwapBytes(ShortValue,2)) m_ThumbNail.nPlanes = BitConverter.ToInt16(ShortValue,0);
int nTotalData = m_ImageResource.nSize - 28; // header
byte [] buffer = new byte[nTotalData];
byte c;
if(m_ImageResource.nID == 1033)
{
// In BGR format
for(int n=0; n<nTotalData; n=n+3)
{
c = binReader.ReadByte();
nBytesRead += 1;
buffer[n+2] = c;
c = binReader.ReadByte();
nBytesRead += 1;
buffer[n+1] = c;
c = binReader.ReadByte();
nBytesRead += 1;
buffer[n] = c;
}
}
else if(m_ImageResource.nID == 1036)
{
// In RGB format
for (int n=0; n<nTotalData; ++n)
{
c = binReader.ReadByte();
nBytesRead += 1;
buffer[n] = c;
}
}
}
break;
case 1037:
{
IntValue = binReader.ReadBytes(4);
if(SwapBytes(IntValue,4)) m_nGlobalAngle = BitConverter.ToInt32(IntValue,0);
nBytesRead += 4;
}
break;
case 1046:
{
ShortValue = binReader.ReadBytes(2);
nBytesRead += 2;
if(SwapBytes(ShortValue,2)) m_nColourCount = BitConverter.ToInt16(ShortValue,0);
}
break;
case 1047:
{
ShortValue = binReader.ReadBytes(2);
nBytesRead += 2;
if(SwapBytes(ShortValue,2)) m_nTransparentIndex = BitConverter.ToInt16(ShortValue,0);
}
break;
default:
{
byte c;
for(int n=0; n<m_ImageResource.nSize; ++n )
{
c = binReader.ReadByte();
nBytesRead += 1;
}
}
break;
}
}
}
}
bSuccess = true;
}
catch(EndOfStreamException e)
{
bSuccess = false;
MessageBox.Show("Exception occurs while reading image resources: {0}", e.GetType().Name);
}
return bSuccess;
}
private void AddThumbNail()
{
ThumbNail.Add("href", "");
}
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);
}
