In the actual context I have three listboxes, if i selected one item in the first listbox, the selectedindexhanged event is raised to get the neccessary details for the selected item in the first listbox and post the resulsts in the second listbox. the same scenario for the second listbox, if the item is selected in the second listbox, postback is done to get the details to fill in the third listbox. all the three controls are in the same which is shown as follows
listbox1 onselectedindexchanged1
listbox2 onselectedindexchanged2
listbox3