您可以使用此方法来获取数量数组值，例如:

you can use this approach to get the quantity arrays values like:

var quantityArray = $("input[name='quantity[]']")
                    .map(function(){return $(this).val();}).get();

并计算总和:

var quantity = quantityArray.reduce(function(a, b) {
                    return parseInt(a, 10) + parseInt(b, 10);
                });