Databases :: Pass Value Into Stored Procedure?

var a=conn.getData2();//getting the value from a global class conn.cs
OracleConnection con = conn.s();
OracleCommand oc = new OracleCommand("logedin(I need to pass the value here)", con);

logedin is strored procedure :-

create procedure logedin(user_id in int)
as
begin
update user_details set status='logedin'
where userid=user_id;
end;

i would lke to pass the value into the stored proc that was retrieved by the variable into the database.