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JQuery caching elements, difference between $ variable and variable?

I was wondering if anyone could explain the difference in element caching in JQuery. One with and without a dollar sign.

Here's an example:

var cached = $('.someElement'); 

var $cached = $('.someElement');
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2 answers


There is no difference . Both are cached, but only the variable name is different.

Both cached

and $cached

are valid variables Javascript:

var $message = 'Hello';
var message = 'Hello';


The $ variable syntax is often used to indicate that a variable contains a jQuery object and not another type (string, integer, DOM element, ...). It's a kind of Hungarian notation, but it's just a convention among programmers. Nothing Javascript or jQuery overlays.

When people talk about caching a jQuery variable, they only mean doing the search once :

//Like this: cached: search is done once.
var clientSpan = $('#client');
clientSpan.hide();
clientSpan.show();
// ...

//Not like this: uncached
$('#client').hide();
$('#client').show();
// ...
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The prefix is $

used to denote that the variable contains a jQuery object. In terms of code, there is no difference, both elements in your example are now contained in a jQuery object inside each variable.

For example:



var myVariable = $("#myElement").text(); // string
var $myVariable = $("#myElement"); // jQuery object
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