How to pass multple parameters to a web form

I have a page I want to use as a pre-filter with 6 dropdowns. The user can select one or more of the ddls before clicking on a button to open the next form. What is the best way to pass the parameters? All values are integers and the stored procedure will return all records if a zero is passed in. I was thinking that I would evaluate each ddl before sending and if the user did not make a selection then I would assign the  parameter as zero for the ddl. Thanks for any help
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