jqGrid ASP.NET WebForms cellurl不起作用

Question

我想在网格中编辑我的数据。我可以在表格中编辑它并看到它，但我不会去c＃方法。我尝试使用ajax但它也不起作用...序列化也不起作用。有什么问题？

    [WebMethod]
    public static string LoadData()
    {
        SqlConnection cn = new SqlConnection(ConfigurationManager.ConnectionStrings["conn"].ConnectionString);
        SqlDataAdapter da = new SqlDataAdapter("SELECT * from Employees", cn);
        DataSet ds = new DataSet();
        da.Fill(ds);
        return JsonConvert.SerializeObject(ds.Tables[0]);
    }

    [WebMethod]
    public void UpdateGrid()
    {
        //code to actually do the update to the database
        SqlConnection cn = new SqlConnection(ConfigurationManager.ConnectionStrings["conn"].ConnectionString);
        SqlDataAdapter da = new SqlDataAdapter("SELECT * from Employees", cn);
    }
}

和JS：

$(document).ready(function () {
        $("#btnEmployee").click(function () {
            var service = "Default.aspx/LoadData";
            var lastsel2;
            $.ajax({
                url: service,
                datatype: "json",
                data: "{}",
                contentType: "application/json; charset=utf-8",
                method: "POST",
                success: function (result) {
                    result = result.d;
                    jQuery("#EmpTable").jqGrid({
                        datatype: "local",
                        colNames : ['Emp numb', 'First name', 'Second name', 'Salary'],
                        colModel: [
                            { name:"Emp_id", index: "Emp_id", width:80, editable: true},
                            { name: "First_name", index: "First_name", width: 80, editable: true},
                            { name: "Second_name", index: "Second_name", width: 80, editable: true},
                            { name: "Salary", index: "Salary", width: 80, editable: true}
                        ],
                        data: JSON.parse(result),
                        rowNum: 10,
                        loadonce: true,
                        rowList: [5, 10, 20],
                        pager: '#EmpPager',
                        viewrecords: true,
                        sortorder: 'asc',
                        gridview: true,
                        autowidth: true,
                        sortname: 'Emp_id', 
                        altRows: true,
                        hoverrows: true, 
                        onSelectRow: function (id) {
                            if (id && id !== lastsel2) {
                                jQuery('#EmpTable').restoreRow(lastsel2);
                                jQuery('#EmpTable').editRow(id, true);
                                lastsel2 = id;
                            }

                        },
                        caption: "Events",
                        cellurl: 'Default.aspx/UpdateGrid'
                    });
                    $("#EmpTable").jqGrid('navGrid', '#EmpPager', { edit: true, add: true, del: false });
                    $("#EmpTable").jqGrid('inlineNav', "#EmpPager");

                    },
                error: function (error) {
                    alert("Oops!");
                }
            });
        });             
    });