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CWindowDC Class

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The latest version of this topic can be found at CWindowDC Class.

Derived from CDC.

Syntax

class CWindowDC : public CDC

Members

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.

Remarks

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.

Inheritance Hierarchy

CObject

CDC

CWindowDC

Requirements

Header: afxwin.h

CWindowDC::CWindowDC

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);

CWindowDC::m_hWnd

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.

See Also

CDC Class
Hierarchy Chart
CDC Class