void CtestThubnailView::ShowThubnail( CDC * pDC, CString fileName )
{

    LPSHELLFOLDER pIShellFolder = NULL;

    CString sParentFolder = GetPath( fileName );
    if (sParentFolder.IsEmpty())
    {
        return ;
    }

    LPSHELLFOLDER pIDesktopFolder = NULL;
    HRESULT hRes = SHGetDesktopFolder(&pIDesktopFolder);
    if (FAILED(hRes))
    {
        return ;
    }

    LPITEMIDLIST pidl = GetPIDL(sParentFolder, pIDesktopFolder);
    if (NULL == pidl)
    {
        return ;
    }

    hRes = pIDesktopFolder->BindToObject(pidl, NULL, IID_IShellFolder, (void**)&pIShellFolder);
    if (FAILED(hRes))
    {
        return ;
    }

    LPMALLOC pMalloc;
    if (SHGetMalloc (&pMalloc)== NOERROR)
    {
        pMalloc->Free(pidl);
        pMalloc->Release();
    } else
    {
        return ;
    }
    CString sRelFileName = GetName( fileName );
    LPCITEMIDLIST relativePidl = GetPIDL(sRelFileName, pIShellFolder);

    if (NULL == relativePidl)
    {
        pIShellFolder->Release();
        return ;
    }

    SIZE size;
    size.cx = GetSystemMetrics(SM_CXSCREEN) ; 
    size.cy = GetSystemMetrics(SM_CYSCREEN) ;


    LPEXTRACTIMAGE pIExtract = NULL;
    HRESULT hr;
    hr = pIShellFolder->GetUIObjectOf(NULL, 1, &relativePidl, IID_IExtractImage,
        NULL, (void**)&pIExtract);
    if(NULL == pIExtract) // early shell version, thumbs not supported
    {
        return ;
    }

    OLECHAR wszPathBuffer[MAX_PATH];
    DWORD dwPriority = 0; // IEI_PRIORITY_NORMAL is defined nowhere!
    DWORD dwFlags =  IEIFLAG_SCREEN;
    HBITMAP hBmpImage = NULL;
    hr = pIExtract->GetLocation(wszPathBuffer, MAX_PATH, &dwPriority,
        &size, 32, &dwFlags);
    // even if we've got shell v4.70+, not all files support thumbnails 

    if(NOERROR == hr) 
    {
        try{

            hr = pIExtract->Extract(&hBmpImage);
            CString strTmp;
            strTmp.Format( "Extract file %S ok! \n" , wszPathBuffer );
            TRACE( strTmp );
        }
        catch(...)
        {
            CString strTmp;
            strTmp.Format( "Extract file %S error! \n" , wszPathBuffer );
            TRACE( strTmp );
            
        }
    }
    pIExtract->Release();

    if (NULL == hBmpImage )
    {
        pIShellFolder->Release();
        LPMALLOC pMalloc;
        if (SHGetMalloc (&pMalloc)== NOERROR)
        {
            pMalloc->Free((void*)relativePidl);
            pMalloc->Release();
        }
        return ;
    }

    pIShellFolder->Release();
    
    if (SHGetMalloc (&pMalloc)== NOERROR)
    {
        pMalloc->Free((void*)relativePidl);
        pMalloc->Release();
    }

    
    CBitmap bitmap;
    bitmap.Attach( hBmpImage );
    CDC   dcComp;   
    dcComp.CreateCompatibleDC(pDC);   
    dcComp.SelectObject(&bitmap);   
    //   get   size   of   bitmap   for   BitBlt()   
    BITMAP   bmInfo;   
    bitmap.GetObject(sizeof(bmInfo),&bmInfo);   
    //   use   BitBlt()   to   draw   bitmap   
    pDC->BitBlt(0,0,bmInfo.bmWidth,bmInfo.bmHeight,   
        &dcComp,   0,0,SRCCOPY);
    
    DeleteObject( hBmpImage );
    
}