jQuery add elements to empty selection?

Question

Why doesn\'t this work?

var spans = $();
var elem = document.getElementById(\'someId\');
spans.add(elem);

What is the proper way to start

Answer 1

Quoting from the jQuery website:

Given a jQuery object that represents a set of DOM elements, the .add() method constructs a new jQuery object from the union of those elements and the ones passed into the method.

Hence, when you do .add() it will not save the added elements, you would have to explicitly assign the element to the newly created object i.e

var $elements = $('.elements');
$elements = $elements.add($('#anotherelement'));

Answer 2

Try

var spans = $("<span />");
var elem = $("#someId").html();
spans.append(elem).appendTo('#someAnotherId');

instead

Answer 3

I guess I don't get what you're asking. If you have an element and you want to add it to a collection, you just use the .add() method just like you've already shown. What confuses some is that this returns a new jQuery object so you would do it like this:

var spans = $();
var elem = document.getElementById('someId');
spans = spans.add(elem);

Of course, something like this would be shorter:

var spans = $();
spans = spans.add('#someId');

And, of course, you don't have to start with an empty object. You would just start with:

var spans = $('#someId');