Can only set text of one label in a page

Question

I have a pretty strange problem. I have two fields where I can enter values, and then I want to show calculated values in two seperate labels (different calculations).

However, only one of the values is being shown right now.

HTML:

<input id="btcowned" />


<p>
    Fee<br />
    <input id="feebox" value="4.5" />
</p>

<p>
    Transfer
<label id="totalnetworth" style="font-weight: bold;" />
    (no vat)<br />
    <label id="totalnetworthVat" style="font-weight: bold;" />
    (vat)<br />
</p>

JAVASCRIPT:

<script>
    $(document).ready(function() {
        $('#btcowned').keyup(function() {
            updateNumbers();
        });
        $('#feebox').keyup(function() {
            updateNumbers();
        });


    });

    function updateNumbers() {
        var chosen = $('#btcowned').val();
        var fee = parseFloat($('#feebox').val());

        var val = chosen - ((chosen * fee) / 100);
        var vatVal = val * (1 + 0.025);

        $('#totalnetworth').text(val);
        $('#totalnetworthVat').text(vatVal);

        alert(vatVal);

    }
</script>

The totalnetworth works great and show the calculated value. The totalnetworthVat shows nothing. I also tried even simpler things than writing vatVal, like $('#totalnetworthVat').text('foo').

However nothing shows, and FireBug shows no JS errors.

My alert() shows that vatVal is a real number.

Any ideas?

Answer 1

I think the problem is the self-closing tag:

<label id="totalnetworth" style="font-weight: bold;" />

If you change it to:

<label id="totalnetworth" style="font-weight: bold;"></label>

...it then seems to work: http://jsfiddle.net/GRFda/

My understanding is that self-closing tags like you had won't work unless the doc type is xhtml, and even then it probably won't work if the page isn't served with a MIME type of text/xml or application/xhtml+xml.

Answer 2

I have made quite a bunch of calculators, that is why I gave it a little bit more work.

Look at my solution in jsFiddle.

<style type='text/css'>
table td,
table th {
    border: 1px solid #DDD;
    padding: 2px 5px;
}
.totalnetworth .value {
    font-weight: bold;
}
</style>
<script type='text/javascript'>//<![CDATA[ 
$(window).load(function(){
$(document).ready(function () {
    $('.btcowned').keyup(updateNumbers);
    $('.feebox').keyup(updateNumbers);
});
function updateNumbers(e) {
// Preparation
var $calc = $(this).closest('.calculator'),
    $results = $calc.find('table'),
    chosen = parseFloat($calc.find('.btcowned').val()),
    fee = parseFloat($calc.find('.feebox').val()),
    vatPercent = 25,
// Calculation
    vatRate = vatPercent * 0.01 + 1,
    val = chosen - ((chosen * fee) / 100),
    vatVal = val * vatRate;
// Representation
$results.find('.totalnetworth .novat').html(isNaN(val) ? '-' : Number(val).toFixed(2));
$results.find('.totalnetworth .wvat').html(isNaN(vatVal) ? '-' : Number(vatVal).toFixed(2));
}
});//]]>
</script>
<div class="calculator">
    <label for="btcowned-1">btcowned
        <input id="btcowned-1" class="btcowned" value="" />
    </label>
    <label for="btcowned-1">Fee
        <input id="feebox-1" class="feebox" value="4.5" />
    </label>
    <table>
        <tr>
            <th>Title</th>
            <th>Cost</th>
            <th>Cost+VAT</th>
        </tr>
        <tr class="totalnetworth">
            <td>Transfer</td>
            <td class="novat value"></td>
            <td class="wvat value"></td>
        </tr>
    </table>
</div>

And some comments regarding your code:

1. Don't use ID's for your scripts;
2. Close only void tags like area, base, br, col, embed, hr, img, input, keygen, link, menuitem, meta, param, source, track, wbr;
3. Don't trust user input to give correct data format, as it can crash your scripts with ease;
4. Always try to separate preparation and calculation part from representation part in your scripts, that will make it cleaner and it will be much easier to catch bugs.