js 分页。类似这种（前展示3页，后展示3页），5 6 7 [8] 9 10 11

js_page.js

/**
 * 页码显示插件
 * @author imzhi
 * @date 2015-06-01
 *
 * @param total 总条数
 * @param per 每页条数
 * @param current 当前页码
 * @return {string} str 返回页码字串
 */
function pagebar(total, per, current) {
    var side = 3; // 两边分别展示3页
    var start = 1;
    var end = Math.ceil(total / per);
    var s_dis = current - start;
    var e_dis = end - current;
    var s_page = current - side < 1 ? 1 : current - side,
        e_page = current + side > end ? end : current + side;
    var i;
    var arr = [];

    if (end > 2 * side + 1) {

        if (s_dis < side) {

            e_page = side - s_dis + current + side > end ? end : side - s_dis + current + side;

        } else if (e_dis < side) {

            s_page = current - side - side + e_dis < 1 ? 1 : current - side - side + e_dis;

        }

    }


    for (i = s_page; i <= e_page; i++) {
        arr.push(i);
    }

    return arr.join(",");
}