Question

<div id="table">
<input type="checkbox" class="db2applforce kon" value="15010" title="to be forced">

Neither of these work. It returns always 0 instead of the correct number.

alert($("#table").find(".kon :checkbox").length);

alert($("#table").find(":checkbox").find(".kon").length);

Can I do ‘all in one’ query?

Answer 1

Radek,
In your selector, you should not have a space between .kon and :checkbox. This tries to find a div with the class kon and inside of it a checkbox. Since your checkbox is of the class kon, do the following instead:

alert($("#table").find(".kon:checkbox").length);

This yields the right answer. Also, you should always close your divs, i.e.:

<div id="table">
<input type="checkbox" class="db2applforce kon" value="15010" title="to be forced">
</div>

For the sake of completeness and further clarity, if your block of HTML had looked like this:

<div id="table">
    <div class='kon'>
        <input type="checkbox" class="db2applforce" value="15010" title="to be forced">
    </div>
</div>

then your first selector above would have worked, and your second one would have worked if swapped:

alert($("#table").find(".kon").find(":checkbox").length);