how to add the textbox value and id another table.

List<int> list = new List<int>();
            for (int i = 0; i < 1; i++)
            {
                TextBox tb = (TextBox)Page.Form.FindControl(("txt" + i));
                string value = tb.Text;

                arrLIst.Add(value);//hear i get textbox value

           }
           string num1 = Convert.ToString(arrLIst[0]);
           

            SqlDataAdapter adp = new SqlDataAdapter("select id from Tll where type_id = 56 ", con);
            DataSet ds = new DataSet();
            adp.Fill(ds);
            adp.Dispose();

            string valu12 = Convert.ToString(ds.Tables[0].Rows[0]["id"]);//here i get id of table

        }