Question

I’m running a really simple jQuery script to grab all emails selected by checkboxes in a table. The table looks like this:

<table>
    <tbody>
        <tr>
            <td>
                <input type="checkbox" value="MD5HASH" />
            </td>
            <td>
                First Name
            </td>
            <td class="email">
                Email Address
            </td>
        </tr>
    </tbody>
</table>

My jQuery looks like this:

$("#submitButton").click(function() {
    var output = [];
    $("table tbody tr:has(input:checkbox:checked)").each(function() {
        var email = $('td.email', $(this)).text();
        if (validate(email) && output.indexOf(email) == -1)
            output.push(email);
    }); 

    $("#emails").val(output.join(", "));
});

function validate(email) {
    return /[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*@(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?/.test(email); 
}

This fails miserably in IE, but works everywhere else.

1. The table tbody tr:has(input:checkbox:checked) selector matches nothing.
2. The call to validate throws a Object expected error.

WHY!? Isn’t jQuery designed to be cross-browser and portable?

Answer 1

Internet Explorer (< 9) doesn’t have Array.prototype.indexOf. Try using jQuery’s $.inArray instead (it’s cross browser and will actually use Array.prototype.indexOf if it exists :-P).

if (validate(email) && $.inArray(email,output) == -1)
  output.push(email);