Javascript 计算分页

var getPageData = function (last_page, current_page) {
        var numberLinks = [];
        var i = 0;
        for (i; i < last_page; i++) {
            var num = i + 1;
            var f = Math.abs(current_page - num);
            if (f < 4) { // 左3页，右3页
                numberLinks.push(num);
            }
        }

        return numberLinks;
    };