jQuery $(document).ready and UpdatePanels?

Question

I'm using jQuery to wire up some mouseover effects on elements that are inside an UpdatePanel. The events are bound in $(document).ready . For example:

$(function() {    
    $('div._Foo').bind("mouseover", function(e) {
        // Do something exciting
    });    
});

Of course, this works fine the first time the page is loaded, but when the UpdatePanel does a partial page update, it's not run and the mouseover effects don't work any more inside the UpdatePanel.

What's the recommended approach for wiring stuff up in jQuery not only on the first page load, but every time an UpdatePanel fires a partial page update? Should I be using the ASP.NET ajax lifecycle instead of $(document).ready?

Answer 1

I would use one of the following approaches:

1. Encapsulate the event binding in a function and run it every time you update the page. You can always contain the event binding to specific elements so as not to bind events multiple times to the same elements.

2. Use the livequery plug-in, which basically performs method one for you auto-magically. Your preference may vary depending on the amount of control you want to have on the event binding.

Answer 2

FWIW, I experienced a similar issue w/mootools. Re-attaching my events was the correct move, but needed to be done at the end of the request..eg

var prm = Sys.WebForms.PageRequestManager.getInstance();
prm.add_endRequest(function() {... 

Just something to keep in mind if beginRequest causes you to get null reference JS exceptions.

Cheers

Answer 3

User Control with jQuery Inside an UpdatePanel

This isn't a direct answer to the question, but I did put this solution together by reading the answers that I found here, and I thought someone might find it useful.

I was trying to use a jQuery textarea limiter inside of a User Control. This was tricky, because the User Control runs inside of an UpdatePanel, and it was losing its bindings on callback.

If this was just a page, the answers here would have applied directly. However, User Controls do not have direct access to the head tag, nor did they have direct access to the UpdatePanel as some of the answers assume.

I ended up putting this script block right into the top of my User Control's markup. For the initial bind, it uses $(document).ready, and then it uses prm.add_endRequest from there:

<script type="text/javascript">
    function BindControlEvents() {
        //jQuery is wrapped in BindEvents function so it can be re-bound after each callback.
        //Your code would replace the following line:
            $('#<%= TextProtocolDrugInstructions.ClientID %>').limit('100', '#charsLeft_Instructions');            
    }

    //Initial bind
    $(document).ready(function () {
        BindControlEvents();
    });

    //Re-bind for callbacks
    var prm = Sys.WebForms.PageRequestManager.getInstance(); 

    prm.add_endRequest(function() { 
        BindControlEvents();
    }); 

</script>

So... Just thought someone might like to know that this works.

Answer 4

function pageLoad() is very dangerous to use in this situation. You could have events become wired multiple times. I would also stay away from .live() as it attaches to the document element and has to traverse the entire page (slow and crappy).

The best solution I have seen so far is to use jQuery .delegate() function on a wrapper outside the update panel and make use of bubbling. Other then that, you could always wire up the handlers using Microsoft's Ajax library which was designed to work with UpdatePanels.

Answer 5

This is a great plugin for use with update panels:

http://updatepanelplugin.codeplex.com/

Answer 6

Sys.Application.add_load(LoadHandler); //This load handler solved update panel did not bind control after partial postback
function LoadHandler() {
        $(document).ready(function () {
        //rebind any events here for controls under update panel
        });
}