exports.getAllStudent = function (req, res) {
    //拿到参数
    var rows = url.parse(req.url, true).query.rows;
    var page = url.parse(req.url, true).query.page;
    var sidx = url.parse(req.url, true).query.sidx;
    var sord = url.parse(req.url, true).query.sord;

    var sordNumber = sord == "asc" ? 1 : -1;

    //分页算法
    Student.count({}, function (err, count) {
        //总页数
        console.log(count)
        var total = Math.ceil(count / rows);
        console.log(total)
      
        var sortobj = {};
        //动态绑定一个键
        sortobj[sidx] = sordNumber;
        //这是一个结合了排序、分页的大检索
        //为什么要暴露records、page、total、rows这些键，都是jqGrid要求的
        //请看     http://blog.mn886.net/jqGrid/ ，  左侧点击新手demo
        //它的API：http://blog.mn886.net/jqGrid/JSONData
        /* Student.find({},function (err,results) {
             //console.log(results);
             res.json({"records" : count, "page" : page, "total" : total , "rows" : results});
         });*/
 
      
        /*.sort(sortobj)*/
        Student.find({}).limit(rows).skip(rows * (page - 1)).exec(function (err, results) {
            console.log(rows,page);
            console.log(results)
            res.json({"records": count, "page": page, "total": total, "rows": results});
        });
    });
};