asp.net-mvc – Controller Action方法仅在第一次获得.它为什么

$(document).ready(function () {

            $('#FilterButton').click(function () {

                alert('button clicked');

                var myGrid = jQuery("#list").jqGrid({
                    url: '/Data/GridData/',datatype: 'json',mtype: 'POST',......

这是请求的操作方法

[HttpPost]
    public JsonResult GridData(string sidx,string sord,int page,int rows,string species,string methodOfTake,string outputType,string seasons,string years)
    {          

        var results = (from a in db.t_harvest_statistics_elk
                        where a.year == "2008" && a.unit_number == 1
                        orderby a.id
                        select new { a.id,a.year,a.unit_number,a.total_hunters,a.bulls,a.cows }).ToList(); 

        int pageIndex = Convert.ToInt32(page) - 1;
        int pageSize = rows;
        int totalRecords = results.Count();   
        int totalPages = (int)Math.Ceiling((float)totalRecords / (float)pageSize);

        var pageResults = results.Skip(pageIndex * pageSize).Take(pageSize);           

        var jsonData = new
        {
            total = totalPages,page,records = totalRecords,rows = (
                from pageResult in pageResults
                select new
                {
                    id = pageResult.id,cell = new[] { 
                                    pageResult.year.ToString(),"Add",pageResult.unit_number.ToString(),pageResult.total_hunters.ToString(),pageResult.bulls.ToString(),"add",pageResult.cows.ToString(),"add"

            }
                }).ToArray()
        };


        return Json(jsonData,JsonRequestBehavior.AllowGet); 
    }