System.NullReferenceException: Object reference not set to an instance of an object.
at _ricerca.get_drop_values(String table_name, String text_field_name, String value_field_name, String default_name, String default_value, String where_cond) in c:\inetpub\wwwroot\nauticaffari\ricerca.aspx.cs:line 455
select distinct ID, cat_nome from categoria_off order by cat_nome