C#界面畫虛線且無

 private void labelbar11_Paint(object sender, PaintEventArgs e)
        {
            Pen pen1 = new Pen(Color.Black, 3);
            pen1.DashStyle = System.Drawing.Drawing2D.DashStyle.Dash;
            pen1.DashPattern = new float[] { 4f, 2f };
            e.Graphics.DrawRectangle(pen1, 0, 0, this.panel1.Width - 1, this.panel1.Height - 1);

        }