如何加粗数据表列

我有一个查询，我想要加粗datatable列之一。怎么做呢

"Dear " + dtdoc.Rows[i]["ToUser"].ToString() + ",  <br /><br /> " +

我想在asp.net

中将To_User显示为粗体

My Subject part bold is not working

public void TransferMail()
{
    string conString = string.Empty;
    try
    {
        conString = System.Configuration.ConfigurationManager.ConnectionStrings["ConnectionString"].ToString();
    }
    catch (Exception ex)
    {
        ex.Message.ToString();
    }

    string strsql = "Select a.Last_To_User,a.disp_through,a.to_user,a.to_department,a.mkey, k.first_name + ' ' + d.last_name TransferFrom, "+
                    "a.party_name, a.doc_no Inward_No, c.type_desc Doc_Type, a.ref_no,  "+
                      "convert(varchar(25),a.ref_date,103) Ref_date, " +
                             " a.Inward_amt,  "+
                             " case when a.disp_through ='DP' then d.first_name + ' ' + d.last_name "+
                             " else b.first_name + ' ' + b.last_name end ToUser  "+
                         " from inward_doc_tracking_hdr a "+
                        " left join user_mst b on a.To_User = b.mkey "+
                        "left join user_mst d on a.Last_To_User = d.mkey "+
                      "  left join user_mst k on a.User_Id = k.mkey "+
                     "  inner join type_mst_a c "+
                    "  on a.doc_type = c.master_mkey    " +
                      "and a.mkey = " + Request.QueryString["Inward_Mkey"].ToString() + " ";
    DataTable dtdoc = new DataTable();
    using (SqlConnection conn = new SqlConnection(conString))
    {
        conn.Open();
        using (SqlDataAdapter dbdata = new SqlDataAdapter(strsql, conn))
        {
            dbdata.Fill(dtdoc);
        }
        conn.Close();
    }
    DataSet ds = new DataSet();
    ds.Tables.Add(dtdoc);
    ds.Tables[0].TableName = "Transfer Mailer";
    if (dtdoc != null && dtdoc.Rows.Count > 0)
    {
        for (int i = 0; i < dtdoc.Rows.Count; i++)
        {
            string StrPriBody = "Dear <b>" + dtdoc.Rows[i]["ToUser"].ToString() + "</b>,  <br /><br /> " +
                                "This is to inform you that <b>" + dtdoc.Rows[i]["Inward_No"].ToString() + "</b> has been  " +
                                "transferred to you by <b>" + dtdoc.Rows[i]["TransferFrom"].ToString() + "</b> <br /><br />" +

                                "Inward No: <b>" + dtdoc.Rows[i]["Inward_No"].ToString() + "</b> <br />" +
                                "Party: <b>" + dtdoc.Rows[i]["party_name"].ToString() + "</b> <br />" +
                                "Doc Type: <b>" + dtdoc.Rows[i]["Doc_Type"].ToString() + "</b> <br />" +
                                "Doc Ref No.: <b>" + dtdoc.Rows[i]["Ref_no"].ToString() + "</b> <br />" +
                                "Date: <b>" + dtdoc.Rows[i]["ref_date"].ToString() + "</b> <br />" +
                                "Amount: <b>" + dtdoc.Rows[i]["Inward_amt"].ToString() + "</b>  <br /><br /> " +
                                "Kindly update the same in the system. <br /><br />" +
                        "<b>THIS IS A SYSTEM GENERATED MAIL. PLEASE DO NOT REPLY.</b>";
            MailMessage mail = new MailMessage();
            mail.Subject = "Transfer of document <b>" + dtdoc.Rows[i]["Inward_No"].ToString() + " </b> for processing.";
            mail.From = new MailAddress("xxxxxxxxxx");
            SmtpClient smtp = new SmtpClient();
            smtp.Timeout = 1000000;
            smtp.Port = Convert.ToInt32(System.Configuration.ConfigurationManager.AppSettings["Port"]);
            smtp.UseDefaultCredentials = true;
            smtp.Host = System.Configuration.ConfigurationManager.AppSettings["MailHost1"];
            smtp.Credentials = new NetworkCredential(mail.From.ToString(), "PS123456");
            smtp.EnableSsl = true;
            mail.To.Add(new MailAddress("XXXXXXxx"));
            mail.IsBodyHtml = true;
            mail.Body = StrPriBody;
            smtp.Send(mail);
        }
    }
}

"Dear <b>" + dtdoc.Rows[i]["ToUser"].ToString() + "</b>,  <br /><br /> " +

"Dear <strong>" + dtdoc.Rows[i]["ToUser"].ToString() + "</strong>,  <br /><br /> " +

mail.IsBodyHtml = true;