C / C++ / MFC

// Create a normal DC and a memory DC for the entire screen. The 
// normal DC provides a "snapshot" of the screen contents. The 
// memory DC keeps a copy of this "snapshot" in the associated 
// bitmap. 
 
hdcScreen = CreateDC("DISPLAY", NULL, NULL, NULL); 
hdcCompatible = CreateCompatibleDC(hdcScreen); 
 
// Create a compatible bitmap for hdcScreen. 
 
hbmScreen = CreateCompatibleBitmap(hdcScreen, 
                     GetDeviceCaps(hdcScreen, HORZRES), 
                     GetDeviceCaps(hdcScreen, VERTRES)); 
 
if (hbmScreen == 0) 
    errhandler("hbmScreen", hwnd); 
 
// Select the bitmaps into the compatible DC. 
 
if (!SelectObject(hdcCompatible, hbmScreen)) 
    errhandler("Compatible Bitmap Selection", hwnd); 
 
        // Hide the application window. 
 
        ShowWindow(hwnd, SW_HIDE); 
 
         //Copy color data for the entire display into a 
         //bitmap that is selected into a compatible DC. 
 
        if (!BitBlt(hdcCompatible, 
               0,0, 
               bmp.bmWidth, bmp.bmHeight, 
               hdcScreen, 
               0,0, 
               SRCCOPY)) 
 
        errhandler("Screen to Compat Blt Failed", hwnd); 
 
        // Redraw the application window. 
 
        ShowWindow(hwnd, SW_SHOW); 

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void CTestView::OnInsertText() <br />
{<br />
<br />
  CNewString	dlg;<br />
<br />
  CEdit *pEdit = (CEdit*) &GetEditCtrl();<br />
  ASSERT(pEdit);<br />
 <br />
  UINT result = dlg.DoModal();<br />
	<br />
  if(result==IDOK){<br />
			<br />
	m_NewString += dlg.m_String; <br />
	pEdit->SetWindowText(m_NewString);<br />
			<br />
	pEdit->LineScroll(1); // This should scroll one line down!?<br />
						<br />
  }<br />
	<br />
}<br />
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