how to add data from data souce to reportviwer

 if (ds.Tables[0].Rows.Count > 0)
            {
               
                ReportDataSource ds1 = new ReportDataSource("DataSet1_devicevoltagereport", ds.Tables[0]);
                rptvolvstime.LocalReport.DataSources.Clear();
                rptvolvstime.LocalReport.DataSources.Add(ds1);
                rptvolvstime.Visible = true;
                btnpdf.Visible = true;

            }
            else
            {
                lbldevup.Visible = true;
                lbldevup.Text = "No Data Found:";
                btnpdf.Visible = false;
            }