Format summary field

Hi,

I need to put the summary field in group footer area and format it. I saw this discussion How to format the summary field in GROUP? but how to do this: "use FieldObject class and embed the summary field's primary detail to FieldObject" programmatically.

I tried this but it doesn't work:

CrystalDecisions.ReportAppServer.ReportDefModel.FieldObject fi = new CrystalDecisions.ReportAppServer.ReportDefModel.FieldObject();

fi.Left = 500;

CrystalDecisions.ReportAppServer.DataDefModel.SummaryField summaryField = new CrystalDecisions.ReportAppServer.DataDefModel.SummaryField();

 

summaryField.SummarizedField = fieldToSummarize;

summaryField.Group = boGroup;

summaryField.Operation = (CrystalDecisions.ReportAppServer.DataDefModel.CrSummaryOperationEnum)elem.TypeCumul;

fi =(CrystalDecisions.ReportAppServer.ReportDefModel.FieldObject) summaryField; // this line generates error

                           

report.DataDefController.SummaryFieldController.Add(indexSummaryField, summaryField);

report.ReportDefController.ReportObjectController.Add(fi, section2, -1);

Thanks in advance.