addcomment function

[eluser]junaids[/eluser]
hi
i have a page with url like
http://localhost/codeigniter/index.php/e...iewevent/8

it shows an event detail from the DB. the page has a textarea to add comments. on submittion addcomment() function is called in the contrller. Now i need to know in my controller to which event i have to add comments. i am using code like.

Code:

$Event_id = $this->uri->segment(3, 0);

but it is giving me Event_id= 0 every time, which should be 8 in this case.
any suggestions?