Jquery – An update panel, a postback and jQuery

asp.net-ajaxjquerypostback

An update panel, a postback and jQuery. Sounds like a bad joke,
but here's my situation.

I've got two grids wrapped up in a MS update panel. The grids each
have buttons in them that cause postback events to happen. under one
grid is a div which is hidden by a jQuery function. And in one grid
is a hyperlink which can cause that hidden div to show. Inside of the
hidden div is a asp:button used for another postback.

Now is when I run into a problem. When I click either one of the
buttons inside the grids, my div which is hidden by jQuery shows
up. I don't want it to show up. In fact it should stay hidden until
I call the method to make it show up. The hyperlink click event for
the div does work, it's just that on a postback, the hidden div
shows. Anyone know what could be causing this? Am I missing something
on the postback or do I need more in the document.ready section of the
jquery. Or is the MS ajax update panel screwing with things.

Here's a snippet of the jQuery to hide the div:

$(document).ready(function() {
   $("#actionDiv").hide();                 
});

Best Answer

$(document).ready() won't fire after an MS AJAX panel is updated. If you can set the css on actionDiv before it goes to the browser that would be better for that issue.

Related Solutions

Javascript – n “exists” function for jQuery

In JavaScript, everything is 'truthy' or 'falsy', and for numbers 0 means false, everything else true. So you could write:

if ($(selector).length)

You don't need that >0 part.

Javascript – Add table row in jQuery

The approach you suggest is not guaranteed to give you the result you're looking for - what if you had a tbody for example:

<table id="myTable">
  <tbody>
    <tr>...</tr>
    <tr>...</tr>
  </tbody>
</table>

You would end up with the following:

<table id="myTable">
  <tbody>
    <tr>...</tr>
    <tr>...</tr>
  </tbody>
  <tr>...</tr>
</table>

I would therefore recommend this approach instead:

$('#myTable tr:last').after('<tr>...</tr><tr>...</tr>');

You can include anything within the after() method as long as it's valid HTML, including multiple rows as per the example above.

Update: Revisiting this answer following recent activity with this question. eyelidlessness makes a good comment that there will always be a tbody in the DOM; this is true, but only if there is at least one row. If you have no rows, there will be no tbody unless you have specified one yourself.

DaRKoN_ suggests appending to the tbody rather than adding content after the last tr. This gets around the issue of having no rows, but still isn't bulletproof as you could theoretically have multiple tbody elements and the row would get added to each of them.

Weighing everything up, I'm not sure there is a single one-line solution that accounts for every single possible scenario. You will need to make sure the jQuery code tallies with your markup.

I think the safest solution is probably to ensure your table always includes at least one tbody in your markup, even if it has no rows. On this basis, you can use the following which will work however many rows you have (and also account for multiple tbody elements):

$('#myTable > tbody:last-child').append('<tr>...</tr><tr>...</tr>');

Best Answer

Related Solutions

Javascript – n “exists” function for jQuery

Javascript – Add table row in jQuery

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