using System;using System.Collections.Generic;using System.ComponentModel;using System.Data;using System.Drawing;using System.Text;using System.Windows.Forms;using System.Drawing.Drawing2D;namespace advanced_drawing{  public partial class Form6 : Form  {    public Form6()    {      InitializeComponent();    }    private void button1_Click(object sender, EventArgs e)    {      for (int i = 0; i <= 90; i += 10)      {        Matrix matrix = new Matrix();        matrix.Rotate(i);        Graphics g = this.CreateGraphics();        g.Transform = matrix;        g.DrawLine(Pens.Blue, 0, 0, 250, 0);        g.DrawString("zhuzhao", this.Font, Brushes.Blue, new RectangleF(250, 0, 100, 100));      }    }  }}