C#指纹仪 代码走不进去 是为何？

SqlCommand sqlFingerCheck = new SqlCommand("select [D_id],[D_name],[Fingerprint],[CI_time],[GO_time] from T_Doctor where [Fingerprint]<>'' and GETDATE() between CI_time and GO_time", conn);
                    SqlDataReader sdr = sqlFingerCheck.ExecuteReader();

                    if (!sdr.HasRows)
                    {
                        //g = p.CreateGraphics();
                        g.DrawString("有效期内没有信息！", new Font("黑体", 15, FontStyle.Bold), new SolidBrush(Color.Red), new Point(p.Width / 2, p.Height / 2));

                    }
                    else
                    {
                        while (sdr.Read())//用sqldatareader必须用
                        {

                            //g = p.CreateGraphics();
                            oFinger = sdr["Fingerprint"].ToString();

                            if (axZKFPEngX1.VerFingerFromStr(ref oFinger, Ntemp, false, ref temp))
                            {
                                FingerGot = true;
                            }                          

                        }
                        if (FingerGot)
                        {
                            g.DrawString("√", new Font("黑体", 60, FontStyle.Bold), new SolidBrush(Color.Green), new Point(p.Width / 2, p.Height / 2));
                        }
                        else
                        {
                            g.DrawString("×", new Font("黑体", 60, FontStyle.Bold), new SolidBrush(Color.Red), new Point(p.Width / 2, p.Height / 2));
                        }
                    }
                    g.Dispose();
                    conn.Close();
                }