javascript, sum of Label

Question

I have in a table, several label ex:

<td style="width:10%"><label id="PrecoProd_3" class="negrito">R$ 1.502,25</label></td>

There are several lines with this type, changing only id

I’d like to put it down at a certain place on page one <label></label> with the total sum

I could do jquery, pure javascript, anyway, but I haven’t been able to isolate the fields, since I don’t know the ID (can have several lines, so I can’t refer to the label id (I believe)

tried to do so

 function id(el) {
        return document.getElementById(el);
    }
    function somaLabel() {
        //Produtos - é o ID da tabela,
        var inputs = id('Produtos').getElementsByTagName('label');

        var soma = 0;
        for (var i = 0; i < inputs.length; i++) {
            soma += parseInt(inputs[i].value);
        }
        alert(soma);
        //id('resultado').value = soma;
    }

Alert is giving NAN Alert just for testing, because I tried to do on the final label. Example of the application:

http://fiddle.jshell.net/dorathoto/3xDgX/

Answer 1

The error is on the line

sum += parseint(inputs[i]. value);

The element label does not have the attribute value, the way you’re hoping.

For that, you need to take the text of label, that by DOM, is your first child.

Thus:

soma += parseFloat(inputs[i].firstChild.nodeValue.substr(3).replace(/\./g, "").replace(/,/g, ".")));

• The substr is to skip the beginning of your string "R$ "
• I used parseFloat because of the decimal places
• The replace are to remove the thousand separator (".") and then replace the decimal separator "," for ".", so that the parseFloat can function properly

Also, after reading the whole fiddle, there was an error in the conversion to currency function: missing replace the "." generated by the method toFixed for ",", in addition to correcting the regular expression that adds the thousand separator. The complete fiddle is here.

The final code, already corrected, of the function in question is shown below:

function formatDinheiro(n, currency) {
    //às vezes n vem como NaN, quando o usuário deixa o campo em branco
    if (isNaN(n))
        n = 0;
    //converte n para string com 2 casas decimais
    var x = (currency + " " + n.toFixed(2).replace(/\./g, ",")).split(","),
        x1 = x[0],
        x2 = ((x.length > 1) ? "," + x[1] : ""),
        rgx = /(\d+)(\d{3})/;
    //acrescenta um separador de milhar a cada 3 dígitos
    while (rgx.test(x1))
        x1 = x1.replace(rgx, '$1' + '.' + '$2');
    return x1 + x2;
}

Another mistake is that by doing:

var inputs = id('Products'). getelementsbytagname('label');

The label with the subtotal is also returned in the array, so its value entered the sum again. The corrected code of this function is shown below:

function somaLabelProduto() {
    var inputs = id("Produto").getElementsByTagName('label');

    var soma = 0;
    for (var i = 0; i < inputs.length; i++) {
        if (inputs[i].id != "sub_total_0")
            soma += parseFloat(inputs[i].firstChild.nodeValue.substr(3).replace(/\./g, "").replace(/,/g, "."));
    }

    document.getElementById('sub_total_0').innerHTML = formatDinheiro(soma, "R$");
}