// Add to Cart JS/jQ code:
jQuery.ajax({
    url: '/Common/BasketSVC.asmx/AddQtyToCart',
    data: JSON.stringify({
        _ProductId: 888888,
        qty: 1,
        autoDelivery: false,
        freq: 1,
        elementAction: 1
    }),
    dataType: "json",
    contentType: "application/json;",
    type: 'POST',
    success: function() { /* either do something(); or return; */ }
});