Question

I’ve a set of checkboxes and also a main checkbox, If I check main chekbox then the rest will be checked but I can check one by one. So I’ve a Link and I want to show that link only if one or more checkboxes are checked, how?

EDIT:
This is the HTML code for test:

<table width="100%">
    <thead>
        <tr>
            <td style="text-align:center;"><input type="checkbox" name="message_delivery" /></td>
            <td>Asunto</td>
            <td>Para</td>
            <td>Fecha</td>
        </tr>
    </thead>
    <tbody>
        <tr>
            <td><input type="checkbox" name="message_delivery[]" value="1" /></td>
            <td><a href="messages/show/id/1" class="read">sadasdasdas</a></td>
            <td>Demo Demo</td>
            <td>Wednesday, 05 de September de 2012 - 11:51:19 AM</td>
        </tr>
        <tr>
            <td><input type="checkbox" name="message_delivery[]" value="1" /></td>
            <td><a href="messages/show/id/1" class="read">sadasdasdas</a></td>
            <td>170ead917-FN 170ead917-LN</td>
            <td>Wednesday, 05 de September de 2012 - 11:51:19 AM</td>
        </tr>
        <tr>
            <td><input type="checkbox" name="message_delivery[]" value="1" /></td>
            <td><a href="messages/show/id/1" class="read">sadasdasdas</a></td>
            <td>Demo1 Lastname1</td>
            <td>Wednesday, 05 de September de 2012 - 11:51:19 AM</td>
        </tr>
        <tr>
            <td><input type="checkbox" name="message_delivery[]" value="1" /></td>
            <td><a href="messages/show/id/1" class="read">sadasdasdas</a></td>
            <td>174889ead-FN 174889ead-LN</td>
            <td>Wednesday, 05 de September de 2012 - 11:51:19 AM</td>
        </tr>
    </tbody>
</table>

<div class="button-bar">
    <a href="http://cmv.loc/messages/add">Escribir nuevo</a>
    <a id="btn_delete" class="btn_delete" style="display:none">Borrar marcados</a>
</div>

I want to show #btn_delete if one or more checkboxes are checked.

Cheers and thanks in advance

Answer 1

$(':checkbox').click(function() {
    $('a').toggle($(':checkbox:checked').length > 0);
});​

http://jsfiddle.net/zerkms/RpxZd/1/