You can use
rptDoc.PrintToPrinter
method to directly print crystal report.
Add these lines at the end of your report printing funtion
System.Drawing.Printing.PrintDocument printDocument = new System.Drawing.Printing.PrintDocument();
rptDoc.PrintOptions.PrinterName = "Printer Name";
rptDoc.PrintToPrinter(1, true, 0, 0);
Check this article as well
http://www.authorcode.com/how-to-print-crystal-report-without-report-viewer-or-any-print-dialog-in-c/[
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