Mschar winform下 简易实现选择范围内图像放大

       bool can_fit = false;  //判断鼠标按下
        int x1 = 0;
        int y1 = 0;    //鼠标焦点左上角
        double x_begin = 0;

        double y_end = 0;   //chart坐标左上角

   private void Form1_Load(object sender, EventArgs e)

{

    for (double i = 1; i < 20; i++)
                {
                    chart1.Series["Series1"].Points.AddXY(i, i);   /////简单初始化 chart
                }

}

//chart 鼠标按下事件

    private void chart1_MouseDown(object sender, MouseEventArgs e)
        {

            x1 = e.X;
            y1 = e.Y;
            x_begin = chart1.ChartAreas["ChartArea1"].AxisX.PixelPositionToValue(Convert.ToDouble(x1));   //鼠标焦点坐标 转换为chart坐标
            y_end= chart1.ChartAreas["ChartArea1"].AxisY.PixelPositionToValue(Convert.ToDouble(y1));
            can_fit = true;

        }

//chart 鼠标移动事件

        private void chart1_MouseMove(object sender, MouseEventArgs e)
        {

            {

                if (can_fit)
                {
                    int x = e.X;
                    int y = e.Y;
                    double xx = chart1.ChartAreas["ChartArea1"].AxisX.PixelPositionToValue(Convert.ToDouble(x));
                    double yy = chart1.ChartAreas["ChartArea1"].AxisY.PixelPositionToValue(Convert.ToDouble(y));
                    label1.Text = xx.ToString() + " " + yy.ToString();
                    this.Refresh();
                    Pen blackPen = new Pen(Color.Red, 2);
                    blackPen.DashStyle = System.Drawing.Drawing2D.DashStyle.Dash;
                    chart1.CreateGraphics().DrawRectangle(blackPen, x1, y1, x - x1, y - x1);   //矩形框

                }

            }

        }

//chart 鼠标松开事件

  private void chart1_MouseUp(object sender, MouseEventArgs e)
        {
            can_fit = false ;
            this.Refresh();
            double   x_end = chart1.ChartAreas["ChartArea1"].AxisX.PixelPositionToValue(Convert.ToDouble(e.X));
            double   y_begin = chart1.ChartAreas["ChartArea1"].AxisY.PixelPositionToValue(Convert.ToDouble(e.Y));
       
            chart1.ChartAreas["ChartArea1"].AxisX.Minimum = Convert.ToDouble(((int)x_begin));
            chart1.ChartAreas["ChartArea1"].AxisY.Minimum = Convert.ToDouble(((int)y_begin));
            chart1.ChartAreas["ChartArea1"].AxisX.Maximum = Convert.ToDouble(((int)x_end));
            chart1.ChartAreas["ChartArea1"].AxisY.Maximum = Convert.ToDouble(((int)y_end));
        }

效果图如下：

放大后：