How can I pass variables from JavaScript to PHP?

Question

I am using jQuery to calculate prices. Here is a small snippet of my JavaScript:

// Prices: radio
var curLam = "gloss";
$("input[name=lamination]").click(function () {
    var gloss = 5;
    var matt = 6;
    if ($(this).val() == 'gloss' && curLam != 'gloss') {
        $('#prices span').text(parseInt($('#prices span').text()) + gloss - matt);
        curLam = 'gloss';
        console.log('1');
    }
    if ($(this).val() == 'matt' && curLam != 'matt') {
        $('#prices span').text(parseInt($('#prices span').text()) - gloss + matt);
        curLam = 'matt';
        console.log('2');
    }
    $("#prices span").each(function () {
        var $priceValue = $(this);
    })
});

This checks to see if a matte or gloss finish has been selected and then it inserts the price into the span within the prices div tag.

I need to know how to assign that price value into a variable which can then be passed on to PHP for my shopping cart.

Answer 1

Generally speaking, you shouldn't return the selected price to the server. HTML forms can be easily faked. It is far safer to send the user's choice back to the server, which also knows how much it should cost.

Basically Javascript validation (which this essentially is) is convenient but shouldn't be trusted. You already have an input for selecting the finish. Just send that back to the server. That way your site will still work (or work better) if the user has Javascript disabled.