CWindowDC Class
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Derived from CDC.
class CWindowDC : public CDC
Public Constructors
| Name | Description |
|---|---|
| CWindowDC::CWindowDC | Constructs a CWindowDC object. |
Protected Data Members
| Name | Description |
|---|---|
| CWindowDC::m_hWnd | The HWND to which this CWindowDC is attached. |
Calls the Windows function GetWindowDCat construction time and ReleaseDC at destruction time. This means that a CWindowDC object accesses the entire screen area of a CWnd (both client and nonclient areas).
For more information on using CWindowDC, see Device Contexts.
CWindowDC
Header: afxwin.h
Constructs a CWindowDC object that accesses the entire screen area (both client and nonclient) of the CWnd object pointed to by pWnd.
explicit CWindowDC(CWnd* pWnd);
Parameters
pWnd
The window whose client area the device-context object will access.
Remarks
The constructor calls the Windows function GetWindowDC.
An exception (of type CResourceException) is thrown if the Windows GetWindowDC call fails. A device context may not be available if Windows has already allocated all of its available device contexts. Your application competes for the five common display contexts available at any given time under Windows.
Example
// Get a dc for a CWnd object pointer. CWindowDC dc(pWnd); // Send my private massage. ::SendMessage(pWnd->m_hWnd, WM_MYMESSAGE, 0, 0);
The HWND of the CWnd pointer is used to construct the CWindowDC object.
HWND m_hWnd;
Remarks
m_hWnd is a protected variable of type HWND.
Example
See the example for CWindowDC::CWindowDC.