or
public ParentReport(){ InitializeComponent(); ItemDataBinding += ReportDataBinding;}public void ReportDataBinding(object sender, EventArgs e){ var processingReport = (Telerik.Reporting.Processing.Report)sender; var report = (Telerik.Reporting.Report)processingReport.ItemDefinition; GroupHeaderArea2 = (Telerik.Reporting.GroupHeaderSection)report.Items.Find("GroupHeaderArea2", true)[0]; GroupHeaderArea2.ItemDataBinding += AssignSubReportDataSource;}public void AssignSubReportDataSource(object sender, EventArgs e){ Telerik.Reporting.Processing.GroupSection groupSection = (Telerik.Reporting.Processing.GroupSection)sender; Telerik.Reporting.Processing.TextBox txtName = (Telerik.Reporting.Processing.TextBox)groupSection.ChildElements.Find("txtName", true)[0]; NavigateToReportAction action = (NavigateToReportAction)((Telerik.Reporting.TextBox)txtName.ItemDefinition).Action; InstanceReportSource subReportSource = (InstanceReportSource)action.ReportSource; ((Telerik.Reporting.Report)subreportSource.ReportDocument).NeedDataSource += subReport_NeedDataSource;}protected void subReport_NeedDataSource(object sender, EventArgs e){ ((Telerik.Reporting.Processing.Report)sender).DataSource = this.DataSource;}