One Update Panel vs. Multiple Update Panels
I have an ASP.NET web page that displays a variety of fields that need to be updated best on certain conditions, button clicks and so on. We've implemented AJAX, using the ASP.NET Update Panel to avoid visible postbacks.
Originally there was only one area that needed this ability ... that soon expanded to other fields. Now my web page has multiple UpdatePanels.
I am wondering if it would be best to just wrap the entire form in a single UpdatePanel, or keep the individual UpdatePanels.
What are the best practices for using the ASP.NET UpdatePanel?
If there are pieces of the page that need to be updated together, there are ways to trigger other panels to update when one does.. but you should definitely be using multiple update panels.
I'd caution that with multiple update panels you'll want to be careful. Make sure you set the UpdateMode to Conditional. Otherwise, when one update panel is "posted back" to the server, all of them are posted back.
I'd highly suggest using these tools
Any of these answers don't mentioned maintainabiliy comparison between the choices. Third options is that you don't use any update panel and leave your self to the reverse ajax. Check out the interesting projects: PokeIn and VisualJS.NET
I recommend multiple updatepanels. Using multiple updatepanels will keep alive the true meaning of using updatepanel in asp.net web applications. And since we can even trigger one updatepanel from another updatepanel this makes it easier to code page-wide controls and behaviour.
I completely agree to use Multiple Update Panel rather than to use single update panel,When you want only a certain part to be postbacked if you want entire page to be postback then it is better to use single update panel.
Make sure that you make the updatemode="conditional" for all the updatepanel otherwise all the updatepanel will get refreshed.
Also Check out the below Post for complete usage for update panel
Not sure about the best practices, but in my experience multiple panels work well, and reduce the amount of data being sent at one time - resulting in an increase in response time overall. Multiple panels also reduce the complexity of each server call.