I have imported file from excel to gridview
BarCode     AdmissionNo        RefNo         SName FName
and my code is 
<asp:GridView ID="GridView1" runat="server" Class="table table-striped table-bordered table-hover">
</asp:GridView>
also save this data with the help of this code
    protected void Insert(object sender, EventArgs e)
    {
        try
        {
            string filePath = string.Empty;
            string contenttype = string.Empty;
            string filename = string.Empty;
            byte[] bytes = null;
            filename = "photo.png";
            contenttype = "image/png";
            System.Drawing.Image defaultImage = System.Drawing.Image.FromFile(Server.MapPath("~/Images/photo.png"));
            using (MemoryStream ms = new MemoryStream())
            {
                defaultImage.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);
                bytes = ms.ToArray();
            }
            con = new SqlDbConnect();
            foreach (GridViewRow row in GridView1.Rows)
            {
             
                con.SqlQuery("INSERT INTO tblStdReg (AdmissionNo,ReferenceNo,AdmissionDate,YearID,CourseID,ClassID,SectionID,RollNo,SName,DOB,Gender,BloodGroup,Religion,SCNIC,SPhone,ParentID,FCNIC,FName,FPhone,FJob,MName,MCNIC,MPhone,MJob,Address,GuardianName,GCNIC,GPhone,GAddress,Qualification,Income,Email,BookNo,BookID,BookDate,SPic,SPicName,ContentType) VALUES (@AdNo,@RefNo,@AdDate,@YId,@CId,@ClId,@SId,@Roll,@SN,@dob,@Gen,@BG,@Rel,@SCNIC,@Ph,@PId,@FC,@FN,@FPhone,@FJob,@MN,@MCNIC,@MPhone,@MJob,@Add,@GuardianName,@GCNIC,@GPhone,@GAdd,@Qualification,@Income,@Email,@BookNo,@BookID,@BookDate,@SPic,@SPicName,@ContentType)");
                con.Cmd.Parameters.AddWithValue("@AdNo", row.Cells[0].Text);
                con.Cmd.Parameters.AddWithValue("@RefNo", row.Cells[1].Text);
                con.Cmd.Parameters.AddWithValue("@AdDate", row.Cells[2].Text);
                con.Cmd.Parameters.AddWithValue("@YId", row.Cells[3].Text);
                con.Cmd.Parameters.Add("@SPic", SqlDbType.Binary).Value = bytes;
                con.Cmd.Parameters.Add("@SPicName", SqlDbType.VarChar).Value = filename;
                con.Cmd.Parameters.Add("@ContentType", SqlDbType.VarChar).Value = contenttype;                
                con.NonQueryEx();
            }
            con.conClose();
            ShowMessage("Students Details Imported Successfully...");
            GridView1.Visible = false;
        }
        catch (Exception ex)
        {
            ShowMessage(ex.Message);
        }
    }
Now I want to generate and save Barcode based on AdmissionNo. Barcode should be generate automatically according to AdmissionNo inside gridview before saving each row. how to do it pls