[SSRS] Listing possible report parameter values in a web app

Is it possible?

Lets say i have a report, which has a few parameters that have some queries behind them for possible values.

Is it possible in an asp.net web app to get a list of the possible parameters?
How about if one of the parameters depends on another?

Cheers for any help!

when the page is building run the query to fill a combo box If parameters are required that may be dependent on other parameters you will have to rebuild the pages once the first parameter is picked.