怎么实现一个矩形随着鼠标的移动而移动。本人写了一个，但是出现严重的异常。望大侠解答

如何实现一个矩形随着鼠标的移动而移动。本人写了一个，但是出现严重的错误。望大侠解答。
void   CMy1_1View::OnMouseMove(UINT   nFlags,   CPoint   point)  
{
CClientDC   dc(this);
CBrush   *brush=CBrush::FromHandle((HBRUSH)GetStockObject(NULL_BRUSH));
CBrush   *poldBrush=dc.SelectObject(brush);
CPen   pen(0,0,RGB(0,0,0));
CPen*   poldpen=dc.SelectObject(&pen);

if(m_draw==1)
{ dc.SetROP2(R2_NOT);
// dc.TextOut(oldpoint.x+10,oldpoint.y+10, "zhangpeng ");
dc.Rectangle(oldpoint.x,oldpoint.y,oldpoint.x+100,oldpoint.y+100);
m_draw=0;
}


if(m_draw==0)
{
dc.SetROP2(R2_NOT);
dc.Rectangle(point.x,point.y,point.x+100,oldpoint.y+100);
// dc.TextOut(point.x+10,point.y+10, "zhangpeng ");
m_draw=1;
oldpoint=point;
}


dc.SelectObject(poldpen);

dc.SelectObject(poldBrush);
}
上面是我的做法，但是实现的结果，和预期的有很大出路。

------解决方案--------------------
dc.Rectangle(point.x,point.y,point.x+100,oldpoint.y+100);
换一下试试
dc.Rectangle(point.x,point.y,point.x+100,point.y+100);