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Some questions about 25 jquery tips

I just read this: http://www.tvidesign.co.uk/blog/improve-your-jquery-25-excellent-tips.aspx

And you had some questions about some of the suggested tricks:

9 - Give your selectors context:

What is the difference between using context and using a more specific selector?

Instead of doing

var selectedItem = $('#listItem' + i, $('.myList'));

What about

var selectedItem = $('.myList>#listItem' + i);

Which one is faster / better, or is there no difference?

12 - Learn about event delegation:

I would suggest that with a low number of handlers, the delegation event is slower than normal binding.

How many handlers is the time when you should start using event delegation?

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    var selectedItem = $('.listItem' + i, ctx);
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//LI elems with CSS class "foo"
//but only inside the element with the ID "onlyInHere"
$('li.foo', '#onlyInHere')
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Classes are limited by the type and amount of data that you can (or should) store in them. Data is a more flexible way to store large amounts of state data for HTML elements.

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