How is it possible to pass parameters into a sub report with asp.net?

or

manipulate the sub report selection formula at runtime?

Thanks

Greeting,
I have a similar question -
I had a main report and two identical subreport.
Each report has date parameters From, To.
I don't wnt to enter the same parameters 3 times for each report. How to pass the same parameters from main report to 2 subreports.
I tried to use Subreport Links window to link date parameters, but
subreport did not generate any data after link.
Any ideas?

Thank you,
Violetta