lanshengsheng

在視圖類中添加私有bool類型的m_bDraw,m_bDraw在視圖類構造函數中初始化為FALSE.在OnLButtonDown和OnLButtonUp消息函數中分別設置為TRUE和FALSE。
在視圖類添加私有CPoint類型m_ptOld,在OnLButtonDown消息函數中初始化這個變量m_ptOld=point;
void CTestView::OnMouseMove(UINT nFlags, CPoint point) 

{

// TODO: Add your message handler code here and/or call default

//扇形

CClientDC dc(this);

//SetROP2設置繪圖模式函數

//dc.SetROP2(R2_BLACK);

//dc.SetROP2(R2_MERGENOTPEN);

CPen pen(PS_SOLID,1,#ff0000);

CPen *pOldpen=dc.SelectObject(&pen);

if(TRUE==m_bDraw)

{

dc.MoveTo(m_ptOrigin);

dc.LineTo(point);

dc.LineTo(m_ptOld);

m_ptOld=point;

}

dc.SelectObject(pOldpen);

//連續線條

/*

CClientDC dc(this);

CPen pen(PS_SOLID,3,#ff0000);

CPen *pOldPen=dc.SelectObject(&pen);

if(TRUE==m_bDraw)

{

dc.MoveTo(m_ptOrigin);

dc.LineTo(point);

m_ptOrigin=point;

}

dc.SelectObject(pOldPen);

*/

CView::OnMouseMove(nFlags, point);

}