Ajax调用不刷新网格

Question

我在我的项目中遇到了这个问题，因为我只是重新生成相同的问题，我创建了测试项目，但问题仍然存在。

我有一个网格视图。我最初用一些值绑定它，点击按钮后，我用不同的数据源绑定它。但它显示了相同的数据。

C＃：

public partial class Default : System.Web.UI.Page
    {
        static Default def;
        protected void Page_Load(object sender, EventArgs e)
        {
            grdTest.DataSource = new List<Employee> { 
                                     new Employee {Age = "26", Gender = "Male", Name = "A"},
                                     new Employee {Age = "26", Gender = "Male", Name = "B"},
                                     new Employee {Age = "26", Gender = "Male", Name = "C"}
                                    };
            grdTest.DataBind();
            def = this;

        }

        public void Bind()
        {
             GridView gr = (GridView)def.FindControl("grdTest");
             gr.DataSource = null;

             gr.DataSource = new List<Employee> { 
                                     new Employee {Age = "26", Gender = "Male", Name = "A"},
                                     new Employee {Age = "26", Gender = "Male", Name = "B"},
                                     new Employee {Age = "26", Gender = "Male", Name = "C"},
                                     new Employee {Age = "26", Gender = "Male", Name = "D"}
                                    };
             gr.DataBind();
        }

        [WebMethod]
        public static void TestMethod()
        {
            def.Bind();
        }
    }
    public class Employee
    {
        public string Name { get; set; }
        public string Gender { get; set; }
        public string Age { get; set; }
    }

JQuery的：

$(document).ready(function () {
            $("[id*=btnTest]").click(
                function () {
                    $.ajax({
                        type: "POST",
                        url: "Default.aspx/TestMethod",
                        contentType: "application/json; charset=utf-8",
                        dataType: "json",
                        // Passes id of current instance of user control
                        //data: "{ 'currentId': '" + $(input).attr("id").split("_").reverse()[1] + "' }",
                        success: function (response) {
                        },
                        failure: function (response) {
                        }
                    });
                });
        });