jQuery select by attribute using AND and OR operat

Question

I'm thinking about, if it is possible in jQuery to select elements by named attributes using AND and OR.

Example:

<div myid="1" myc="blue">1</div>
<div myid="2" myc="blue">2</div>
<div myid="3" myc="blue">3</div>
<div myid="4">4</div>

I'd like to select all the elements where myc="blue" but only those with myid set to either 1 or 3.

So I tried:

a=$('[myc="blue"] [myid="1"]  [myid="3"]');

but it does not work, same here:

a=$('[myc="blue"] && [myid="1"] || [myid="3"]');

Is it possible without writing special filter functions?

Answer 1

First find the condition that occurs in all situations, then filter the special conditions:

$('[myc="blue"]')
    .filter('[myid="1"],[myid="3"]');

Answer 2

To properly select the elements using the logical operations that you've stated, you just need jQuery.filter() for the AND operation, not "special filter functions". You also need jQuery.add() for the OR operation.

var elements = $('[myc="blue"]').filter('[myid="1"').add('[myid="3"');

Alternatively, it is possible to accomplish using shorthand in a single selector, where jamming selectors together acts as an AND and separating with a comma acts as an OR:

var elements = $('[myc="blue"][myid="1"], [myid="3"]');