客户区也能移动整个窗口实现

oid CMainFrame::OnLButtonDown(UINT nFlags, CPoint point) 

{

    if (!IsZoomed() && !IsIconic())

    {

        SendMessage(WM_NCLBUTTONDOWN, HTCAPTION, MAKELPARAM(point.x, point.y));

    }

    CUIWnd::OnLButtonDown(nFlags, point);

}