How to know whether <div id="target"> is shown or not with jQuery?

Question

I tried $.isshown() but there is not this function

Answer 1

I think this should work:

$(elem).is(":visible");

Answer 2

use the :visible selector:

if($('div#target:visible').length){
    alert('target is visible');
}

edit: use Quintin Robinson's solution, it's much clearer