C / C++ / MFC

void CScrollBarEx::OnLButtonDown(UINT inFlags, CPoint inPoint) {
...
				CaptureAnImage(sliderVector[m_currentSlider-1].sliderRect);
...
}

int CScrollBarEx::CaptureAnImage(RECT sliderRect)
{
    //HDC hdcScreen;
    HDC hdcWindow;
    HDC hdcMemDC = NULL;
    HBITMAP hbmScreen = NULL;
    BITMAP bmpScreen;

	HBITMAP m_hAndMask;
	HBITMAP m_hXorMask;


    // Retrieve the handle to a display device context for the client 
    // area of the window. 
    //hdcScreen =  (GetDC())->GetSafeHdc();
    hdcWindow = (GetDC())->GetSafeHdc();

    // Create a compatible DC which is used in a BitBlt from the window DC
    hdcMemDC = CreateCompatibleDC(hdcWindow); 


    if(!hdcMemDC)
    {
       // MessageBox(hWnd, L"CreateCompatibleDC has failed",L"Failed", MB_OK);
        goto done;
    }

    // Get the client area for size calculation
    RECT rcClient;
    GetClientRect(&rcClient);

    
	/*
	//This is the best stretch mode
    SetStretchBltMode(hdcWindow,HALFTONE);

    //The source DC is the entire screen and the destination DC is the current window (HWND)
    if(!StretchBlt(hdcWindow, 
               sliderRect.left ,sliderRect.top, 
               sliderRect.right, sliderRect.bottom, 
               hdcWindow, 
               0,0,
               GetSystemMetrics (SM_CXSCREEN),
               GetSystemMetrics (SM_CYSCREEN),
               SRCCOPY))
    {
        //MessageBox(hWnd, L"StretchBlt has failed",L"Failed", MB_OK);
        goto done;
    }
    */
	

    // Create a compatible bitmap from the Window DC
		//hbmScreen = CreateCompatibleBitmap(hdcWindow, rcClient.right-rcClient.left, rcClient.bottom-rcClient.top);
	
	    //hbmScreen = CreateCompatibleBitmap(hdcWindow, sliderRect.right, sliderRect.bottom-sliderRect.top);
		
	    hbmScreen = CreateCompatibleBitmap(hdcWindow, sliderRect.right-sliderRect.left, sliderRect.bottom-sliderRect.top);

    
    if(!hbmScreen)
    {
        //MessageBox(hWnd, L"CreateCompatibleBitmap Failed",L"Failed", MB_OK);
        goto done;
    }

	// Select the compatible bitmap into the compatible memory DC.
    SelectObject(hdcMemDC,hbmScreen);

    // Bit block transfer into our compatible memory DC.
    if(!BitBlt(hdcMemDC, 
               0,0,
               sliderRect.right-sliderRect.left, sliderRect.bottom-sliderRect.top, 
               hdcWindow, 
               sliderRect.left,sliderRect.top,
               SRCCOPY))
    {
        //MessageBox(hWnd, L"BitBlt has failed", L"Failed", MB_OK);
        goto done;
    }

	
	// Get the BITMAP from the HBITMAP
    GetObject(hbmScreen,sizeof(BITMAP),&bmpScreen);

	
    BITMAPFILEHEADER   bmfHeader;    
    BITMAPINFOHEADER   bi;
     
	
	bi.biSize = sizeof(BITMAPINFOHEADER);    
    bi.biWidth = bmpScreen.bmWidth;    
    bi.biHeight = bmpScreen.bmHeight;  
    bi.biPlanes = 1;    
    bi.biBitCount = 32;    
    bi.biCompression = BI_RGB;    
    bi.biSizeImage = 0;  
    bi.biXPelsPerMeter = 0;    
    bi.biYPelsPerMeter = 0;    
    bi.biClrUsed = 0;    
    bi.biClrImportant = 0;

    DWORD dwBmpSize = ((bmpScreen.bmWidth * bi.biBitCount + 31) / 32) * 4 * bmpScreen.bmHeight;

	// Starting with 32-bit Windows, GlobalAlloc and LocalAlloc are implemented as wrapper functions that 
    // call HeapAlloc using a handle to the process's default heap. Therefore, GlobalAlloc and LocalAlloc 
    // have greater overhead than HeapAlloc.
    HANDLE hDIB = GlobalAlloc(GHND,dwBmpSize); 
    char *lpbitmap = (char *)GlobalLock(hDIB);    
  
	// Gets the "bits" from the bitmap and copies them into a buffer 
    // which is pointed to by lpbitmap.
    GetDIBits(hdcWindow, hbmScreen, 0,
        (UINT)bmpScreen.bmHeight,
        lpbitmap,
        (BITMAPINFO *)&bi, DIB_RGB_COLORS);	

    // A file is created, this is where we will save the screen capture.
    HANDLE hFile = CreateFile(L"capture.bmp",
        GENERIC_WRITE,
        0,
        NULL,
        CREATE_ALWAYS,
        FILE_ATTRIBUTE_NORMAL, NULL);   
    
    // Add the size of the headers to the size of the bitmap to get the total file size
    DWORD dwSizeofDIB = dwBmpSize + sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER);
 
    //Offset to where the actual bitmap bits start.
    bmfHeader.bfOffBits = (DWORD)sizeof(BITMAPFILEHEADER) + (DWORD)sizeof(BITMAPINFOHEADER); 
    
    //Size of the file
    bmfHeader.bfSize = dwSizeofDIB; 
    
    //bfType must always be BM for Bitmaps
    bmfHeader.bfType = 0x4D42; //BM   
 
    DWORD dwBytesWritten = 0;
    WriteFile(hFile, (LPSTR)&bmfHeader, sizeof(BITMAPFILEHEADER), &dwBytesWritten, NULL);
    WriteFile(hFile, (LPSTR)&bi, sizeof(BITMAPINFOHEADER), &dwBytesWritten, NULL);
    WriteFile(hFile, (LPSTR)lpbitmap, dwBmpSize, &dwBytesWritten, NULL);
    
    //Unlock and Free the DIB from the heap
    GlobalUnlock(hDIB);    
    GlobalFree(hDIB);


	//Close the handle for the file that was created
    CloseHandle(hFile);
	
	/*
	//20130216
	//Turn the cursor into a bitmap
	//HANDLE hNewBMP = CopyImage(hbmScreen,IMAGE_BITMAP,0,0,LR_COPYRETURNORG);
	m_hXorMask	  =  NULL;
	m_hAndMask	  =  NULL;
	//CColorCursor::GetMaskBitmaps(hbmScreen,RGB(0,0,0),m_hAndMask,m_hXorMask);
	m_hCursor = CColorCursor::CreateCursorFromBitmap(hbmScreen,RGB(0,0,0),0,0);
	//m_hCursor = CColorCursor::CreateCursorFromBitmap(hNewBMP,RGB(0,0,0),0,0);
	*/


	/*
	//Use Jiju George's bitmap drawing function
	HBITMAP aBMP = GetCursorBitmap();
	m_hCursor = CColorCursor::CreateCursorFromBitmap(aBMP,RGB(0,0,0),0,0);
	*/

	//Load up the file that was created earlier in the function into a bitmap
	//   then use that as the cursor.
	HBITMAP   hBMP; 
	HPALETTE palette;
	LoadBitmapFromBMPFile(L"capture.bmp", &hBMP, &palette);
	m_hCursor = CColorCursor::CreateCursorFromBitmap(hBMP,RGB(0,0,0),0,0);
	
	::SetCursor(m_hCursor); 
    
    //Clean up
done:
    DeleteObject(hbmScreen);
    DeleteObject(hdcMemDC);
    //ReleaseDC(hdcScreen);
    //ReleaseDC(hdcWindow);
    //DeleteObject(hdcScreen);
    DeleteObject(hdcWindow);


    return 0;
}

//////////////////////////////////////////////////////////////////////
//  CreateCursorFromBitmap 
//  Function to create a cursor from HBITMAP. 
//  Pass bitmaps having standard cursor sizes like 16*16, 32*32...
//////////////////////////////////////////////////////////////////////
HCURSOR CColorCursor::CreateCursorFromBitmap(HBITMAP hSourceBitmap,
											 COLORREF clrTransparent,
											 DWORD   xHotspot,DWORD   yHotspot)
{
	HCURSOR hRetCursor = NULL;

	do
	{
		if(NULL == hSourceBitmap)
		{
			break;
		}

		//Create the AND and XOR masks for the bitmap
		HBITMAP hAndMask = NULL;
		HBITMAP hXorMask = NULL;
		GetMaskBitmaps(hSourceBitmap,clrTransparent,hAndMask,hXorMask);
		if(NULL == hAndMask || NULL == hXorMask)
		{
			break;
		}

		//Create the cursor using the masks and the hotspot values provided
		ICONINFO iconinfo = {0};
		iconinfo.fIcon		= FALSE;
		iconinfo.xHotspot	= xHotspot;
		iconinfo.yHotspot	= yHotspot;
		iconinfo.hbmMask	= hAndMask;
		iconinfo.hbmColor	= hXorMask;

		hRetCursor = ::CreateIconIndirect(&iconinfo);

	}
	while(0);

	return hRetCursor;
}