Question

我正在使用Windows窗体图表控件，这是滚轮鼠标事件：

void chart1_MouseWheel(object sender, MouseEventArgs e)
        {
            if (e.Delta < 0)
            {
                chart1.ChartAreas[0].AxisX.ScaleView.ZoomReset();
                chart1.ChartAreas[0].AxisY.ScaleView.ZoomReset();
            }

            if (e.Delta > 0)
            {
                double xMin = chart1.ChartAreas[0].AxisX.ScaleView.ViewMinimum;
                double xMax = chart1.ChartAreas[0].AxisX.ScaleView.ViewMaximum;
                double yMin = chart1.ChartAreas[0].AxisY.ScaleView.ViewMinimum;
                double yMax = chart1.ChartAreas[0].AxisY.ScaleView.ViewMaximum;

                double posXStart = chart1.ChartAreas[0].AxisX.PixelPositionToValue(e.Location.X) - (xMax - xMin) / 4;
                double posXFinish = chart1.ChartAreas[0].AxisX.PixelPositionToValue(e.Location.X) + (xMax - xMin) / 4;
                double posYStart = chart1.ChartAreas[0].AxisY.PixelPositionToValue(e.Location.Y) - (yMax - yMin) / 4;
                double posYFinish = chart1.ChartAreas[0].AxisY.PixelPositionToValue(e.Location.Y) + (yMax - yMin) / 4;

                chart1.ChartAreas[0].AxisX.ScaleView.Zoom(posXStart, posXFinish);
                chart1.ChartAreas[0].AxisY.ScaleView.Zoom(posYStart, posYFinish);
            }
        }

问题出现在图表绘制事件中，当我使用滚轮时我绘制点并用线条连接它们点和线都消失了我不认为它们正在缩放。

Pen pen = new Pen(Color.Blue, 2.5f);
        SolidBrush myBrush = new SolidBrush(Color.Red);
        private void chart1_Paint(object sender, PaintEventArgs e)
        {

            if (paintToCalaculate)
            {
                Series s = chart1.Series.FindByName("dummy");
                if (s == null) s = chart1.Series.Add("dummy");
                drawPoints.Clear();
                s.Points.Clear();
                foreach (PointF p in valuePoints)
                {
                    s.Points.AddXY(p.X, p.Y);
                    DataPoint pt = s.Points[0];
                    double x = chart1.ChartAreas[0].AxisX.ValueToPixelPosition(pt.XValue);
                    double y = chart1.ChartAreas[0].AxisY.ValueToPixelPosition(pt.YValues[0]);
                    drawPoints.Add(new Point((int)x, (int)y));
                    s.Points.Clear();
                }
                paintToCalaculate = false;
                chart1.Series.Remove(s);
            }
            foreach (Point p in drawPoints)
            {
                e.Graphics.FillEllipse(Brushes.Red, p.X - 2, p.Y - 2, 4, 4);
            }
            if (drawPoints.Count > 1)
            {
                e.Graphics.DrawLines(pen, drawPoints.ToArray());
            }
                    }

我如何处理滚轮鼠标事件以及我在绘画事件中绘制的点和线？

Answer 1

我认为你可能需要在缩放时设置'paintToCalaculate'标志。它在第一个绘制事件期间关闭，并且在缩放时不会重新打开，因此您的线条不会重新缩放。

如何使用鼠标滚轮缩放Windows窗体图表？

1 个答案: