how to pass parameters to crystal report, please help.
This would entirely depend on crystal reports and you might find informations on crystal reports related communities more likely...I for one have seen crystal reports the last time about 12 years ago. And even back then I simply acknowledged it's existence instead of working with it.
Maybe crystal reports can be invoked via a URL call which would make it simple as you'd need simply build an URL and show the report using web.show_document. But that's pure speculation. Also you might not be the first with this requirement, so the solution to your problem might be right under your nose and just a little google search away ;)