Question about crystal report

Dear all,

I have added a Crystal Report item in my project which is a sales invoice.
There is a field which is the total amount in text format. eg.
SAY UNITED STATES DOLLARS ONE THOUSAND SEVEN HUNDRED SIXTY-NINE ONLY.
I have a method to do it in my class, but I dont know how to include it in
the report. I need to print the invoice in a range, so different invoice
have different total amount. Anyone can give me some suggestion? Thanks a
lot.

Regards,
Kwokho.