绘制NC AREA

CDC* pDC = GetWindowDC();CRgn rgnNC, rgnClient, rgnWindow;rgnNC.CreateRectRgn(0, 0, 0, 0);CRect rcWnd;GetWindowRect(rcWnd);CRect rcClient;GetClientRect(&rcClient);OffsetRect(&rcClient, GetSystemMetrics(SM_CXFRAME), GetSystemMetrics(SM_CYCAPTION));rgnClient.CreateRectRgn(rcClient.left, rcClient.top, rcClient.right, rcClient.bottom);rgnWindow.CreateRectRgn(0, 0, rcWnd.right - rcWnd.left, rcWnd.bottom - rcWnd.top);rgnNC.CombineRgn(&rgnWindow, &rgnClient,RGN_DIFF);CBrush brBackground(RGB(38, 38, 38));pDC->FillRgn(&rgnNC,&brBackground);rgnNC.DeleteObject();brBackground.DeleteObject();