如何使用参数在Picturebox上动态绘制线条？

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

namespace DynamicLineDrawing
{
    public partial class Form1 : Form
    {
        private Point startPoint;
        private Point endPoint;
        private Color lineColor;

        public Form1()
        {
            InitializeComponent();
            startPoint = new Point(50, 50);
            endPoint = new Point(200, 200);
            lineColor = Color.Red;
        }

        private void pictureBox1_Paint(object sender, PaintEventArgs e)
        {
            Graphics g = e.Graphics;
            Pen pen = new Pen(lineColor);
            g.DrawLine(pen, startPoint, endPoint);
        }

        private void button1_Click(object sender, EventArgs e)
        {
            // 更新线条参数的值
            startPoint = new Point(100, 100);
            endPoint = new Point(300, 300);
            lineColor = Color.Blue;

            // 触发重绘
            pictureBox1.Invalidate();
        }
    }
}