ListBox in an UpdatePanel jumps to the top after selecting an item at the bottom?

Question

This only occurs in Internet Explorer. I have a ListBox which is in an UpdatePanel. The ListBox has around 100 items in it and it shows 15 are visible at a time. They are sorted from 1 to 100. If I scroll to the bottom and select item number 50, item 50 stays selected, but the ListBox jumps back to the top of the List, so it is displaying items 1 thru 15. This only happens in Internet Explorer. If I do this in FireFox, the item selected is still displayed, it just becomes the last visible item in the list meaning item 15. Does anyone know a solution to this and why it is happening?

Thanks, XaiSoft

Answer 1

Try setting MaintainScrollPositionOnPostBack="true" in your Page directive (<%@ page %>)

Answer 2

It is happening because when the UpdatePanel updates, it deletes all the existing contents (controls) and recreates them from HTML sent by the server. Control values are included in the update, but things like scroll position are not. The only solution I can think of is to use javascript to record the scroll position before the postback and then restore it after the update panel has finished updating.

Answer 3

This question appears to have been answered in this post:

Maintain scroll position in listboxes in updatepanels, NOT the page