CPoint begin,end;
构造函数中初始化为0;
Cpoint mPoints[100]; //用于记录点坐标
int mPtsNum; //用于表示点个数，构造函数中初始化为0;
void CSssView::OnLButtonDown(UINT nFlags, CPoint point)
{
// TODO: Add your message handler code here and/or call default
begin=point;
CView::OnLButtonDown(nFlags, point);
}
void CSssView::OnLButtonUp(UINT nFlags, CPoint point)
{
// TODO: Add your message handler code here and/or call default
end=point;
CClientDC dc(this);
dc.MoveTo(begin);
dc.LineTo(end);
m_Points[m_PtsNum++] = begin;
m_Points[m_PtsNum++] = end;
CView::OnLButtonUp(nFlags, point);
}
此时不改变窗口的画,可以正常的画出直线.
但是加了OnDraw以后
void CSssView::OnDraw(CDC* pDC)
{
CSssDoc* pDoc = GetDocument();
ASSERT_VALID(pDoc);
// TODO: add draw code for native data here
for(int i=0; i<m_PtsNum; )
{
pDC->MoveTo(m_Points[i++]);
pDC->LineTo(m_Points[i++]);
}}
