How to pass parameter value for a subreport in Crystal Report

To set a parameter value for a parameter field in sub-report of a Crystal Report you may have to use the function

SetParameterValue(string parameterFieldName, object value, string subreport)

First create a ReportDocument object for main report and pass the parameter values to main report and subreports, for instance,

mainrpt = new ReportDocument();
ReportViewer.Enabled = true;
mainrpt.SetParameterValue("@ClmId", CLMID); // main report param
mainrpt.SetParameterValue("@Param1", ParamValue,"SubReport1.rpt"); //subreport param
mainrpt.SetParameterValue("@Param1", ParamValue,"SubReport2.rpt"); //subreport param
ReportViewer.ReportSource = mainrpt;
ReportViewer.Visible = true;