void CSyDlg::OnLButtonDown(UINT nFlags, CPoint point)
{
    // TODO: Add your message handler code here and/or call default
    FILE *fpp;
    CRectTracker RectTracker;
    RECT rc;
    WINDOWPLACEMENT m_Place;

    if(m_bRectSelect==TRUE)
    {
        m_FlameWnd1.GetWindowPlacement(&m_Place);// m_FlameWnd1是当前操作的窗口
        if ((point.x>=m_Place.rcNormalPosition.left)&&(point.x<m_Place.rcNormalPosition.right)&&
            (point.y>=m_Place.rcNormalPosition.top)&&(point.y<m_Place.rcNormalPosition.bottom))
            if (RectTracker.TrackRubberBand(this, point,FALSE))
            {
                m_rSelRect1.left=RectTracker.m_rect.left-m_Place.rcNormalPosition.left;
                m_rSelRect1.right=RectTracker.m_rect.right-m_Place.rcNormalPosition.left;
                m_rSelRect1.top=RectTracker.m_rect.top-m_Place.rcNormalPosition.top;
                m_rSelRect1.bottom=RectTracker.m_rect.bottom-m_Place.rcNormalPosition.top;
                 m_FlameWnd1.GetClientRect(&rc);
                if (m_rSelRect1.left < rc.left)
                    m_rSelRect1.left = rc.left;
                if (m_rSelRect1.top < rc.top)
                    m_rSelRect1.top = rc.top;
                if (m_rSelRect1.right > rc.right)
                    m_rSelRect1.right = rc.right;
                if (m_rSelRect1.bottom > rc.bottom)
                    m_rSelRect1.bottom = rc.bottom;
               }
    }
。。。。。
}
该程序的目的是可以通过鼠标移动重新选择矩形框的位置大小，但在实际应用中，我发现鼠标移动的虚框有问题，所选择的矩形框不对，我是新手啊，麻烦各位了。