How to select items in server side?

Question

i'm using two HTML control type SELECT (selLeft and selRight) in the form. both the SELECT tag property using runat=server Web form page_load i'm loading the details to the selLeft. In client side user press arrow key(button) to selected item move from selLeft to selRight using javascript code. up to this level it's working successfully. :( and to click event i just want enumerate the selRight values, but selRight.item.count is =0 nothing there. how to get the selRight values in sever side button click. pls solution. thanks in advance