Question

mfc 画折线 mousemove实时刷新的问题，我设置的点右键结束画图，但是我只有结束后才能看到线，开始看不到

void CMyView::OnMouseMove(UINT nFlags, CPoint point)
{
// TODO: Add your message handler code here and/or call default
CView::OnMouseMove(nFlags, point);
CMyDoc* pDoc = GetDocument();
ASSERT_VALID(pDoc);
CPoint pt;
CClientDC pdc(this);
Invalidate();
if(m_bFlag==1&&m_nPoint>0)
{
pt=pDoc->m_ptLine[m_nPoint-1];
pdc.MoveTo(pt);
pdc.LineTo(point);
}
}

Answer 1

CView::OnMouseMove(nFlags, point);

CClientDC dc(this);

dc.MoveTo(m_old_pt);
dc.LineTo(point);

m_old_pt = point;