在 Visual Studio 图表中选择时间跨度 (C#)

Question

是否可以（可能使用第三方工具）在图表中添加两条可以移动的线，然后在这两条线的边缘获取两个日期（字符串）？

也许这张图片更好地描述了这个问题。它应该看起来与此类似：

Mockup_picture

已经感谢您的帮助！

Answer 1

您可以尝试通过chart.SelectionRangeChanging事件选择一个时间跨度并获取对应的日期时间。

这是一个代码示例，您可以参考。

private void Form1_Load(object sender, EventArgs e)
        {
            var s = new Series();
            s.ChartType = SeriesChartType.Column;

            var d = new DateTime(2020,10,1);

            s.Points.AddXY(d, 30);
            s.Points.AddXY(d.AddDays(1), 20);
            s.Points.AddXY(d.AddDays(2), 70);
            s.Points.AddXY(d.AddDays(3), 90);
            s.Points.AddXY(d.AddDays(4), 80);
            s.Points.AddXY(d.AddDays(5), 50);
            s.Points.AddXY(d.AddDays(6), 60);
            s.Points.AddXY(d.AddDays(7), 80);
            s.Points.AddXY(d.AddDays(8), 90);

            chart1.Series.Clear();
            chart1.Series.Add(s);


            chart1.Series[0].XValueType = ChartValueType.DateTime;
            chart1.ChartAreas[0].AxisX.LabelStyle.Format = "yyyy-MM-dd";
            chart1.ChartAreas[0].AxisX.Interval = 1;
            chart1.ChartAreas[0].AxisX.IntervalType = DateTimeIntervalType.Days;
            chart1.ChartAreas[0].AxisX.IntervalOffset = 1;

            chart1.Series[0].XValueType = ChartValueType.DateTime;
            DateTime minDate = new DateTime(2020, 10, 01).AddSeconds(-1);
            DateTime maxDate = new DateTime(2020, 10, 08); // or DateTime.Now;
            chart1.ChartAreas[0].AxisX.Minimum = minDate.ToOADate();
            chart1.ChartAreas[0].AxisX.Maximum = maxDate.ToOADate();
            chart1.ChartAreas[0].CursorX.IsUserEnabled = false;         // red cursor at SelectionEnd
            chart1.ChartAreas[0].CursorX.IsUserSelectionEnabled = true;
            chart1.ChartAreas[0].AxisX.ScaleView.Zoomable = false;     // zoom into SelectedRange
            chart1.ChartAreas[0].AxisX.ScrollBar.IsPositionedInside = true;
        }

     
        private void chart1_SelectionRangeChanging(object sender, CursorEventArgs e)
        {
            double x1 = e.NewSelectionStart;
            double x2 = e.NewSelectionEnd;
            DateTime date1 = DateTime.FromOADate(x1);
            DateTime date2 = DateTime.FromOADate(x2);
            txtStart.Text = date1.ToString("yyyy-MM-dd");
            txtEnd.Text = date2.ToString("yyyy-MM-dd");
        }

结果：