how can I save an insert in a txt

I have a problem I can not save a complete insert in a txt, I save it but it saves the parameters not the real values, this is my code

 if (!dao.success) throw new Exception(dao.message);

        //Leer metadatos: Tabla y Campos

        string insert = String.Empty;
        string param = String.Empty;
        string tableName = String.Empty;
        string nombreTable = String.Empty;
        string delete = String.Empty;
        object value = null;
        //DateTime fecha;
        //fecha = DateTime.Now;
        string fecha = DateTime.Now.ToString("yyyy/MM/dd");

        List<Tuple<string, int, object>> tuplas = null;

        foreach (DataRow row in dt.Rows)
        {


            if (!tableName.Equals(row["TableName"].ToString(), StringComparison.OrdinalIgnoreCase))
            {
                if (!String.IsNullOrEmpty(tableName))
                {

                    //Guardar datos en las listas

                    insert = insert.Substring(0, insert.Length - 1) + ") ";
                    param = param.Substring(0, param.Length - 1) + ")";
                    select = select.Substring(0, select.Length - 1) + " FROM " + tableName + " WHERE FECHA_MODIFICACION <=" + "'" + fecha + "'";
                    inserts.Add(insert + param);
                    selects.Add(select);
                    deletes.Add(delete);
                    nombreTables.Add(nombreTable);
                    dao.respaldoRegistrosLog(inserts, selects, tableName, fecha);
                    tableName = String.Empty;

                }

                if (String.IsNullOrEmpty(tableName))
                {
                    tableName = row["TableName"].ToString();
                    tuplas = new List<Tuple<string, int, object>>();

                    //List<object> value = new List<object>(); //OBTENER LISTA DE LOG (Registros)

                    insert = "INSERT INTO " + tableName + " ("; //generaSQL(tableName, tuplas);
                    param = "VALUES (";
                    select = "SELECT ";
                    delete = "DELETE FROM " + tableName + " WHERE FECHA_MODIFICACION <=" + "'" + fecha + "'";
                    nombreTable = "SELECT a.name FROM sys.objects AS a WHERE a.type = 'U' AND a.name LIKE '%_LOG' ORDER BY a.name";
                }
            }



            insert += row["ColumnName"].ToString() + ",";
            select += row["ColumnName"].ToString() + ",";
            param += "@P" + row["ColumnOrder"].ToString() + ",";
            //int columnorder = Convert.ToInt32(row["ColumnOrder"]) - 1;

        }

in this part of the code I assemble the insert with the parameters

and in this other code it is assumed that you should save it in the txt.

origen = new SqlConnection(conexionOrigen);

                    int a = 0;
                    string respaldoLog = ConfigurationManager.AppSettings["rutaRespaldoArchivo"];
                    string rutaCompleta = respaldoLog + "/" + tableName + "_" + fecha + ".txt";


                    foreach (DataRow row in db.Rows)
                    {
                        byte loop = 0;

                        cmd = new SqlCommand(inserts[index]);
                        cmd.Connection = origen;
                        origen.Open();

                        do
                        {

                            foreach (DataColumn dc in db.Columns)
                            {
                                a++;
                                loop++;

                                using (StreamWriter file = new StreamWriter(rutaCompleta, true))
                                {
                                    string nombreParametro = prefijoParametro + (dc.Ordinal + 1).ToString();
                                    cmd.Parameters.AddWithValue(nombreParametro, row[dc.Ordinal]);
                                    file.WriteLine(cmd.Parameters.AddWithValue(nombreParametro, row[dc.Ordinal]));
                                    file.Close();
                                }

                            }


                        } while (loop < 3);



                        origen.Close();


                    }
                }
            }
        }

    }

If someone has any idea or any page to guide me, I would appreciate it.