// private clsMysqlConexion objmysql; private void btBuscar_Click(object sender, EventArgs e) { clsMysqlConexion objmysql = new clsMysqlConexion(); String atributos = "fechayhora,id_linea,id_tarjeta,credito"; String cdgo_t = (CBOX1.Checked) ? tbcdgo.Text : ""; DataTable dt = objmysql.BuscarActividadTbl(atributos, dtinicio, dtfinal, cdgo_t, rbt1.Checked, rbt2.Checked); DataRow[] dr = dt.Select(); decimal fltTotal = 0; for (int i = 0; i < dr.Length; i++) { fltTotal += Convert.ToDecimal(dr[i]["credito"]); } TBOX1.Text = fltTotal.ToString(); dtgv.DataSource = dt; }