Данияр

function load_reservation(stock, year = null, month = null, callback){
        jQuery.ajax({
            method: "POST",
            url: "'.Url::to(['site/ajax-load-reservation']).'",
            data: { "stock": stock, "year": year, "month": month },
            success: function(data) {
                if(data.result==1){
                    callback(data.array);                
                }
                else callback(null);
            },
            dataType: "json",
            async: false
        });

        
    }