MFC之设备描述表DC、画笔Pen、画刷Brush

1.利用SDK全局函数实现画线功能

void CDrawView::OnLButtonUp(UINT nFlags, CPoint point) 
{
    HDC hdc;
    hdc=::GetDC(m_hWnd);
    MoveToEx(hdc,m_ptOrigin.x,m_ptOrigin.y,NULL);
    LineTo(hdc,point.x,point.y);
::ReleaseDC(m_hWnd,hdc);

    CView::OnLButtonUp(nFlags, point);
}

2.利用MFC的CDC类实现画线功能

void CDrawView::OnLButtonUp(UINT nFlags, CPoint point) 
{
 CDC *pDC=GetDC();
    pDC->MoveTo(m_ptOrigin);
    pDC->LineTo(point);
ReleaseDC(pDC);

    CView::OnLButtonUp(nFlags, point);
}

3.利用MFC的CClientDC类实现画线功能

void CDrawView::OnLButtonUp(UINT nFlags, CPoint point) 
{
    CClientDC dc(this);
    CPen *pOldPen=dc.SelectObject(&pen);
    dc.MoveTo(m_ptOrigin);
    dc.LineTo(point);

    CView::OnLButtonUp(nFlags, point);
}

4.利用MFC的CWindewDC类实现画线功能

void CDrawView::OnLButtonUp(UINT nFlags, CPoint point) 
{
    CWindowDC dc(this);
//CWindowDC dc(GetParent());
//CWindowDC dc(GetDesktopWindow());
    dc.MoveTo(m_ptOrigin);
    dc.LineTo(point);

    CView::OnLButtonUp(nFlags, point);
}

5.绘制彩色线条

void CDrawView::OnLButtonUp(UINT nFlags, CPoint point) 
{
    CPen *pOldPen=dc.SelectObject(&pen);
    dc.MoveTo(m_ptOrigin);
    dc.LineTo(point);
    dc.SelectObject(pOldPen);

    CView::OnLButtonUp(nFlags, point);
}

6.使用画刷绘图

void CDrawView::OnLButtonUp(UINT nFlags, CPoint point) 
{
 CBrush brush(RGB(255,0,0));
    CClientDC dc(this);
    dc.FillRect(CRect(m_ptOrigin,point),&brush);

    CView::OnLButtonUp(nFlags, point);
}

7.位图画刷

void CDrawView::OnLButtonUp(UINT nFlags, CPoint point) 
{
    CBitmap bitmap;
    bitmap.LoadBitmap(IDB_BITMAP1);
    CBrush brush(&bitmap);
    CClientDC dc(this);
    dc.FillRect(CRect(m_ptOrigin,point),&brush);

    CBrush *pBrush=CBrush::FromHandle((HBRUSH)GetStockObject(NULL_BRUSH));
    CBrush *pOldBrush=dc.SelectObject(pBrush);
    dc.Rectangle(CRect(m_ptOrigin,point));
    dc.SelectObject(pOldBrush);

    CView::OnLButtonUp(nFlags, point);
}

8.透明画刷

void CDrawView::OnLButtonUp(UINT nFlags, CPoint point) 
{
    CClientDC dc(this);
    CBrush *pBrush=CBrush::FromHandle((HBRUSH)GetStockObject(NULL_BRUSH));
    CBrush *pOldBrush=dc.SelectObject(pBrush);
    dc.Rectangle(CRect(m_ptOrigin,point));
    dc.SelectObject(pOldBrush);

    CView::OnLButtonUp(nFlags, point);
}

9.绘制连续线条

void CDrawView::OnLButtonUp(UINT nFlags, CPoint point) 
{
    m_bDraw=FALSE;

    CView::OnLButtonUp(nFlags, point);
}

void CDrawView::OnMouseMove(UINT nFlags, CPoint point) 
{
    CClientDC dc(this);
if(m_bDraw==TRUE)
    {
        dc.MoveTo(m_ptOrigin);
        dc.LineTo(point);
        m_ptOrigin=point;
    }

    CView::OnMouseMove(nFlags, point);
}

10.绘制扇形效果的线条

void CDrawView::OnLButtonUp(UINT nFlags, CPoint point) 
{
    m_bDraw=FALSE;

    CView::OnLButtonUp(nFlags, point);
}

void CDrawView::OnMouseMove(UINT nFlags, CPoint point) 
{
    // TODO: Add your message handler code here and/or call default
    CClientDC dc(this);
    CPen pen(PS_SOLID,1,RGB(255,0,0));
    CPen *pOldPen=dc.SelectObject(&pen);
    if(m_bDraw==TRUE)
    {
        dc.SetROP2(R2_BLACK);
        dc.MoveTo(m_ptOrigin);
        //dc.LineTo(point);
        dc.LineTo(m_ptOld);
        //dc.MoveTo(m_ptOrigin);
        dc.MoveTo(m_ptOld);
        dc.LineTo(point);
        //m_ptOrigin=point;
        m_ptOld=point;
    }
    dc.SelectObject(pOldPen);
    CView::OnMouseMove(nFlags, point);
}