pass null values

I have a web form that allows a user to do a search, they can select all the
parameters on the web form or only select a few. If the user does not select
a value to search on, how can I pass that to stored procedure and get data
back?
example form:
the user can search on
first name
last name
hire date
termination date
if they only know the first and last name, how can i get data back if the
dates are not entered?see DBNull class
-- bruce (sqlwork.com)
"NuB" <me@.me.com> wrote in message
news:Od3vppMAGHA.2788@.TK2MSFTNGP14.phx.gbl...
>I have a web form that allows a user to do a search, they can select all
>the parameters on the web form or only select a few. If the user does not
>select a value to search on, how can I pass that to stored procedure and
>get data back?
> example form:
> the user can search on
> first name
> last name
> hire date
> termination date
> if they only know the first and last name, how can i get data back if the
> dates are not entered?
>
>