Sono riuscito a fare questo:
codice HTML:
<select name="prova[]">
<option data-id="1" value="50">Single</option>
<option data-id="2" value="225">Single2</option>
</select>
<select name="prova[]">
<option data-id="1" value="15">Single3</option>
<option data-id="2" value="35">Single4</option>
</select>
<span></span>
function sum(x, y) {
var z = x + y;
return z;
}
function calculate() {
var prezzo = [];
var num = [];
$('select').each(function () {
prezzo.push($(this).val());
num.push($(this).data('id'));
});
$('span').text('Totale: '+ sum(prezzo, num));
}
calculate();
$('select').change(function() {
calculate();
});
Ma non mi calcola il totale