Check if element is in a jquery collection

Question

I initialize a jQuery collection like so

$collection = $([])

later on some things happend and I do a lot of

$collection = $collection.add($element)

I do this so that I can call functions like $collection.hide() on all of the elements at once.

The problem is that later I want to do something like _.contains($collection, $element) but this doesn't work. For example:

var $b = $("#content")
var $c = $([]).add(b)
console.log( _.contains($c, $b) )
console.log( _.contains($c.toArray(), $b)

Both evaluate to false.

How can I accomplish my goal with jQuery?

Answer 1

With .is :

if ($c.is($b)) // $c contains $b

Note that .is goes out of its way to make life easy: you can pass a selector (eg "#content" ), or an element (eg document.getElementById("content") ), or a jQuery object (eg $("#content") ) and it will work as expected in each case.