在绘图模型中单击某个数据点时，显示该数据点来自哪个系列的C# (Winforms)

using System;
using System.Windows.Forms.DataVisualization.Charting;

public class MainForm : Form
{
    private Chart chart1;

    public MainForm()
    {
        InitializeComponent();
    }

    private void InitializeComponent()
    {
        this.chart1 = new Chart();
        ((System.ComponentModel.ISupportInitialize)(this.chart1)).BeginInit();
        this.SuspendLayout();
        // 
        // chart1
        // 
        this.chart1.Dock = DockStyle.Fill;
        this.chart1.Location = new System.Drawing.Point(0, 0);
        this.chart1.Name = "chart1";
        this.chart1.Size = new System.Drawing.Size(800, 450);
        this.chart1.TabIndex = 0;
        this.chart1.MouseClick += new System.Windows.Forms.MouseEventHandler(this.chart1_MouseClick);
        // 
        // MainForm
        // 
        this.ClientSize = new System.Drawing.Size(800, 450);
        this.Controls.Add(this.chart1);
        this.Name = "MainForm";
        ((System.ComponentModel.ISupportInitialize)(this.chart1)).EndInit();
        this.ResumeLayout(false);
    }

    private void chart1_MouseClick(object sender, MouseEventArgs e)
    {
        HitTestResult result = chart1.HitTest(e.X, e.Y);
        if (result.ChartElementType == ChartElementType.DataPoint)
        {
            DataPoint dp = (DataPoint)result.Object;
            foreach (Series series in chart1.Series)
            {
                foreach (DataPoint point in series.Points)
                {
                    if (point == dp)
                    {
                        MessageBox.Show($"Data point {dp.YValues[0]} is from series {series.Name}");
                        return;
                    }
                }
            }
        }
    }

    [STAThread]
    static void Main()
    {
        Application.EnableVisualStyles();
        Application.SetCompatibleTextRenderingDefault(false);
        Application.Run(new MainForm());
    }
}