[問題] 用Graphics卻出不來

[hirabbitt (兔子)]

沒有錯誤訊息
但是form裡面沒有圖
做了picturebox之後也沒有
有設point
畫筆也有顏色+有粗度
不知道是哪個步驟弄錯了
QQ

程式碼在下面
因為試了很多方式
所以有點亂

請幫我看一下
謝謝

using System.Drawing;

    public partial class Form1 : Form
    {
        Point p1 = new Point(400, 400);
        Point p2 = new Point(50, 50);
        Point[] p3 = new Point[4];
        Color c1 = Color.Red;
        Pen pe1 = new Pen(Color.Red, 3);

        private Graphics g2;
        private Point point1;

        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            button1.BackColor = c1;
            pe1.DashStyle = System.Drawing.Drawing2D.DashStyle.Dash;
            p3[0] = new Point(0, 0);
            p3[1] = new Point(0, 120);
            p3[2] = new Point(20, 120);
            p3[3] = new Point(20, 0);
        }

        private void button1_Click(object sender, EventArgs e)
        {
            System.Console.WriteLine("X: " + p1.X + ", Y: " + p1.Y);
            Graphics g1 = pictureBox1.CreateGraphics();
            g1.DrawLine(pe1, p1, p2);
            g1.DrawLines(pe1, p3);
        }

        private void pictureBox1_MouseMove(object sender,
System.Windows.Forms.MouseEventArgs e)
        {
            if (e.Button == MouseButtons.Left)
            {
                Pen pen = new Pen(Color.Black, 1);
                Point point2 = new Point(e.X, e.Y);
                g2.DrawLine(pen, point1, point2);
                point1 = new Point(e.X, e.Y);
            }
        }

        private void pictureBox1_MouseDown(object sender,
System.Windows.Forms.MouseEventArgs e)
        {
            g2 = pictureBox1.CreateGraphics();
            point1 = new Point(e.X, e.Y);
        }
    }

--
              ◤  __   ＼__◣     ◢◤◢◤                 ψhirabbitt
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黑兔子我啊           █████ █████     所以所以
                     ██●█● █▇███        
   最喜歡白兔子了    ██╱╲ ●◥█████◣●    我們要一直在一起喔
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◆ From: 163.13.127.91
推 Rezzard:你的程式碼在我的專案能畫出你的需求...
→ Rezzard:你程式有透過事件處理嗎...+= MouseEventHandler( 此類?
→ hirabbitt:這段是我99%的程式碼了耶 沒有用到你說的東西
→ hirabbitt:然後有40%也是複製別人的程式碼 就奇怪怎麼出不來=.=
推 Rezzard:你點pictureBox1屬性裡面有個事件..找MouseDown跟MouseMov
→ Rezzard:連點兩下...事件就會幫你處理進去了 你試看看
→ hirabbitt:有了!!! 大感謝