void Tfrm_BelongFunction::DrawFunction(TCanvas*m_canvas,TRect&m_rect) { TPenStyle style = m_canvas->Pen->Style; TColor color = m_canvas->Pen->Color; m_canvas->Pen->Style = psSolid; m_canvas->Pen->Color =clBlue; if(begin==end) return; AnsiString str = m_strExpress+"[-10,10]"; DrawFunction(m_canvas,m_rect,str); ////////////////////////////// // int sizegrid = 30; double dis = (end-begin)/M; for(double i=0;i<=M;i++) { AnsiString str; str = FloatToStr(begin+dis*i); str = str.FormatFloat("0.00",begin+dis*i); m_canvas->TextOutA(m_rect.Left+i*sizegrid-5,m_rect.Bottom+5,str); } m_canvas->Pen->Style = style; m_canvas->Pen->Color = color; }