Question

This code is fully functional in its job of revealing and hiding containers however the calculations are producing NaN. I have never tried Maths with JQuery before so prehaps one of you can show me where I have wrong.

function product_analysis_global() {
$(':checked').each(function(){
    $('#product_' + this.alt).css('display','block');
    $('#product_quantity_PRI_' + this.alt).val(this.value);
    var quantity = $('#product_quantity_PRI_' + this.alt).val;
    var price = $('#product_price_PRI_' + this.alt).val;
    var duration = $('#product_duration_PRI_' + this.alt).val;
    var dives = $('#product_dives_PRI_' + this.alt).val;
    var hire = $('#product_quantity_PRI_' + this.alt).val;

    $('#product_price_total_PRI_' + this.alt).val(price * quantity);
    $('#product_duration_total_PRI_' + this.alt).val(duration * quantity);
    $('#product_dives_total_PRI_' + this.alt).val(dives * quantity);
    $('#product_hire_total_PRI_' + this.alt).val(hire * quantity);
});
    $(':not(:checked)').each(function(){
        $('#product_' + this.alt).css('display','none');
        $('#product_quantity_PRI_' + this.alt).val('0');
        var quantity = $('#product_quantity_PRI_' + this.alt).val;
        var price = $('#product_price_PRI_' + this.alt).val;
        var duration = $('#product_duration_PRI_' + this.alt).val;
        var dives = $('#product_dives_PRI_' + this.alt).val;
        var hire = $('#product_quantity_PRI_' + this.alt).val;

    $('#product_price_total_PRI_' + this.alt).val(price * quantity);
    $('#product_duration_total_PRI_' + this.alt).val(duration * quantity);
    $('#product_dives_total_PRI_' + this.alt).val(dives * quantity);
    $('#product_hire_total_PRI_' + this.alt).val(hire * quantity);

});
}

Marvellous

Answer 1

All your .vals (without brackets) need brackets after them: (). Otherwise you’re getting the val function rather than the actual value the function returns.

E.g.

var quantity = $('#product_quantity_PRI_' + this.alt).val(); // brackets

---

Also, be careful with .val(), which returns a string. In your scenario, there are no errors here, because you’re only doing multiplication, and the strings will automatically get converted to numbers. But, if you have addition, strings will get concatenated: '1' + '1' = '11'. To prevent this (and be safe even in your example), put a single plus sign in front of the return value from .val() to convert the string into a number:

var quantity = +$('#product_quantity_PRI_' + this.alt).val();