MFC Windows 程序设计源代码,有实用价值

				#include 
				#include 
				#include "RegionDemo.h"
				
				CMyApp myApp;
				
				/////////////////////////////////////////////////////////////////////////
				// CMyApp member functions
				
				BOOL CMyApp::InitInstance ()
				{
				    m_pMainWnd = new CMainWindow;
				    m_pMainWnd->ShowWindow (m_nCmdShow);
				    m_pMainWnd->UpdateWindow ();
				    return TRUE;
				}
				
				/////////////////////////////////////////////////////////////////////////
				// CMainWindow message map and member functions
				
				BEGIN_MESSAGE_MAP (CMainWindow, CFrameWnd)
				    ON_WM_PAINT ()
				END_MESSAGE_MAP ()
				
				CMainWindow::CMainWindow ()
				{
				    Create (NULL, _T ("Region Demo"));
				}
				
				void CMainWindow::OnPaint ()
				{
				    CPaintDC dc (this);
				
					//
				    // Create a 72-point Times New Roman font.
					//
				    CFont font;
				    font.CreatePointFont (720, _T ("Times New Roman"));
				
					//
				    // Create a clipping region from the text string "Hello, MFC."
					//
				    CRect rect;
				    GetClientRect (&rect);
				    CString string ("Hello, MFC");
				
				    CFont* pOldFont = dc.SelectObject (&font);
				    CSize size = dc.GetTextExtent (string);
				    int x = (rect.Width () - size.cx) / 2;
				
					TEXTMETRIC tm;
					dc.GetTextMetrics (&tm);
				    int y = (rect.Height () - tm.tmHeight) / 2;
				
				    dc.BeginPath ();
				    dc.TextOut (x, y, string);
				    dc.EndPath ();
				    dc.SelectObject (pOldFont);
				
				    CRect rcText;
				    CRgn rgn1, rgn2;
				    rgn1.CreateFromPath (&dc);
				    rgn1.GetRgnBox (&rcText);
				    rgn2.CreateRectRgnIndirect (&rcText);
				    rgn1.CombineRgn (&rgn2, &rgn1, RGN_DIFF);
				
				    dc.SelectClipRgn (&rgn1);
				
					//
				    // Draw a radial array of lines.
					//
				    dc.SetViewportOrg (rect.Width () / 2, rect.Height () / 2);
				    double fRadius = hypot (rect.Width () / 2, rect.Height () / 2);
				
				    for (double fAngle = 0.0; fAngle < 6.283; fAngle += 0.01745) {
				        dc.MoveTo (0, 0);
				        dc.LineTo ((int) ((fRadius * cos (fAngle)) + 0.5),
				            (int) ((fRadius * sin (fAngle)) + 0.5));
				    }
				}