TFIleStream Read füllt Buffer nicht

[EWeiss]

Neues Problem neues Thema.

Mein Fortschritt

Delphi-Quellcode:

  if (GetPngAnimation(gp.PngList[SelectedIndex], anih)) then
  begin
    //if FOpen(PWideChar(wsFile), 0, 0, hFileIn) = 0 then
    FileStream := TFileStream.Create(wsFile, fmOpenRead);
    if FileStream.Handle <> 0 then
    begin
      DC := CreateIC('DISPLAY', nil, nil, nil);
      ImgHDC := CreateCompatibleDC(DC);

      hDIB := SKAERO_CreateDIBSection(ImgHDC, anih.Width * anih.Frame, anih.Height, 32);
      SelectObject(ImgHDC, hDIB);
      if GDIP_CreateFromHDC(ImgHDC, Graphics) = OK then
      begin
        BufferSize := FileStream.Size - anih.offset - sizeof(anih) + 1;
        SetLength(sBuffer, BufferSize);
        FileStream.Seek(anih.offset - 1, soFromBeginning);
        FileStream.Read(sBuffer, BufferSize);
        //if FGetAt(FileStream.Handle, anih.offset - 1, sBuffer) = S_OK then
        //begin

FileStream.Read füllt den Buffer nicht fehlt noch was, oder habe ich was übersehen ?

gruss