Try:
For example, you may have an existing formula on your report, @ShipDays, that calculates the number of days it took to ship an order. You can write the following
If-Then-Else formula
to show the words Same Day on the report if @ShipDays is zero, or to show just the contents of the @ShipDays formula if it is not zero:
If {@ShipDays} = 0 Then
"Same Day"
Else
{@ShipDays}
Refer:
If-Then-Else Formulas | Crystal Reports 10: The Complete Reference[
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