如何在windows forms c#中画线？

using System;
using System.Drawing;
using System.Windows.Forms;

public class LineForm : Form
{
    public LineForm()
    {
        // 设置窗体大小和标题
        this.Size = new Size(400, 400);
        this.Text = "画线示例";
    }

    protected override void OnPaint(PaintEventArgs e)
    {
        base.OnPaint(e);

        // 创建一个Graphics对象
        Graphics g = e.Graphics;

        // 创建一个Pen对象，设置线条颜色和宽度
        Pen pen = new Pen(Color.Black, 2);

        // 定义起点和终点坐标
        Point startPoint = new Point(50, 50);
        Point endPoint = new Point(200, 200);

        // 使用Graphics对象的DrawLine方法画线
        g.DrawLine(pen, startPoint, endPoint);

        // 释放资源
        pen.Dispose();
        g.Dispose();
    }

    public static void Main()
    {
        Application.Run(new LineForm());
    }
}