jQuery: finding previous div

Question

<div class="a" style="display:none">Content 1</div>
<div class="a" style="display:none">Content 2</div>

some other HTML...

<span id="b">foobar</span>

How can I match the first div class="a" above the span id="b" to show() it? The id="b" is the only thing I konow before.

Answer 1

$("#b").closest(".a").show();

Try that.

Answer 2

Like this:

$('#b').prevAll('.a:first').show();

Answer 3

Do the elements share an ancestor? If so, you may be able to combine inkedmn's and SLaks's answers:

$('#b').closest('parentType').prevAll('.a:first').show();

Or something similar, depending on your DOM.

Answer 4

As long as I am understanding multiple selectors correctly, this should work. It will get all divs with class 'a' and and the span with the id of 'b'. They will be "in document order" according to the documentation. Then you'll need to get the div prior to your span tag and display it.

var elems = $('span#b, div.a');
var divIndex;
for (var i = 0; i < elems.length; i++)
{
    if (elems[i].tagName == "SPAN")
    {
        divIndex = i - 1;
        break;
    }
}

$(elems[divIndex]).show();