or
private void manPrechodZTable_ItemDataBound(object sender, EventArgs e) { if ((manPrechodZTable.DataSource == null || (manPrechodZTable.DataSource as ExC_BodTrasy.ExC_Prechod[]).Length == 0)) { this.ReportParameters[1].Value = true; } else { this.ReportParameters[1].Value = false; } }public class SurveyListGraphicalCompareModel { public string Question{ get; set; } public Guid? QuestionID { get; set; } public decimal? avgScore { get; set; } public decimal? avgScoreEx { get; set; } }Reporting.GraphicalComparison rapor = new Reporting.GraphicalComparison(); myReport.DataSource = myDataSource; this.ReportViewer1.Report = myReport;