现在的情况是可以打印一个条码标签

调用，PrintDocument.print
如果我要批量实现条码标签的打印，应该怎么写? 
代码如下：

 private void button1_Click(object sender, EventArgs e)     //按钮事件
        {

            strCon = "server=192.168.1.57;uid=sa;pwd=123;database=LonkingJiXie";
            SqlConnection sqlCon = new SqlConnection();
            sqlCon.ConnectionString = strCon;
            sqlCon.Open();
            SqlCommand sqlCom = new SqlCommand("select   * from TestTM", sqlCon);

            SqlDataReader sqlDR = sqlCom.ExecuteReader();


            bool ifcom = sqlDR.Read();
            if (ifcom)
            {
                WLcode = sqlDR[0].ToString();
                WLname = sqlDR[1].ToString();
                TMcode = sqlDR[2].ToString();
            }            

            PrintPreviewDialog ppwDlg = new PrintPreviewDialog();

            PrintDocument prtDoc = new PrintDocument();

            ppwDlg.Document = prtDoc;

            prtDoc.PrintPage += new PrintPageEventHandler(prtDoc_PrintPage);

            if (ppwDlg.ShowDialog() != DialogResult.OK)
            {
                prtDoc.PrintPage -= new PrintPageEventHandler(prtDoc_PrintPage);
                return;
            }


        }

----------------------document.pintpage事件


  //printdocument.printpage 事件

            Graphics g = e.Graphics;

            e.Graphics.Clip = new Region(new Rectangle(10, 2, 800, 200));

            g.PageUnit = GraphicsUnit.Millimeter;

            Font drawFont = new Font("宋体", 14);
            Font drawLGFont = new Font("方正艺黑简体", 8);
            SolidBrush drawBrush = new SolidBrush(Color.Black);

            g.DrawString("Lonking 龙工", drawLGFont, drawBrush, 10, 5);
            SizeF FZ = g.MeasureString("Lonking 龙工", drawFont, e.MarginBounds.Width);

            g.DrawString(WLname + ":", drawFont, drawBrush, 10, 5 + FZ.Height);
            SizeF dd = g.MeasureString(WLname + ":", drawFont, e.MarginBounds.Width);

            g.DrawString(WLcode, drawFont, drawBrush, 10 + dd.Width, 5 + dd.Height);
            Pen penLine = new Pen(new SolidBrush(Color.Black), 0.2f);

            //g.DrawLine(penLine, 10, 10, 190, 10);
            //g.DrawLine(penLine, new PointF(20.0f, Convert.ToSingle(20.0f + dd.Height)), new PointF(Convert.ToSingle(20.0f + 2 * dd.Width), Convert.ToSingle(20.0f + dd.Height)));
            //g.DrawRectangle(penLine, 10,10, 190, 50);   //左，上，右，下   坐标，高、宽


            Code39 _Code39 = new Code39();
            _Code39.Height = 60;
            _Code39.Magnify = 1;
            _Code39.ViewFont = new Font("宋体", 10);

            System.Drawing.Image _CodeImage = _Code39.GetCodeImage(TMcode, Code39.Code39Model.Code39Normal, true);

            g.DrawImage(_CodeImage, 5, 10 + FZ.Height);