How to load RPT file to reportdocument object in WPF C#

I am trying to load rpt file to ReportDocument object for direct printing without viewing rpt file in CrystalReportsViewer.

I have tried the following code but I am getting error "LOAD REPORT FAILED". Kindly help me. Thanks

PrintDialog printDialog1 = new PrintDialog();
ReportDocument report = new ReportDocument();

if (printDialog1.ShowDialog() == true)
{
       report.PrintOptions.PrinterName = printDialog1.PrintQueue.Name;
       report.PrintOptions.PaperSize = (CrystalDecisions.Shared.PaperSize)System.Drawing.Printing.PaperKind.Legal;
       report.Load("invoice.rpt");
       report.PrintToPrinter(2, false, 0, 0);
       myview.view.ViewerCore.ReportSource = report;
       myview.view.ToggleSidePanel = SAPBusinessObjects.WPF.Viewer.Constants.SidePanelKind.None;
}