如何在c#中的图片框中绘制多个矩形？

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

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }

    private void pictureBox1_Paint(object sender, PaintEventArgs e)
    {
        // 创建一个Graphics对象
        Graphics g = e.Graphics;

        // 创建一个Pen对象，用于绘制矩形的边框
        Pen pen = new Pen(Color.Red, 2);

        // 定义矩形的位置和大小
        Rectangle rect1 = new Rectangle(10, 10, 100, 50);
        Rectangle rect2 = new Rectangle(50, 100, 150, 80);

        // 绘制矩形
        g.DrawRectangle(pen, rect1);
        g.DrawRectangle(pen, rect2);

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