Ajax请求不会从控制器返回成功

Question

我有一个onchange事件，当选择一个新的下拉列表项时，它将向控制器发出ajax请求。控制器返回一个模型，其中包含填充第二个下拉列表的新数据......这一切都发生在jQuery PopUp中，因此我的目标是使用新内容重新填充div，但Ajax中的成功函数永远不会被触发..这个逻辑应该用一个视图来替换pop up div，该视图具有基于角色下拉列表选择的新员工下拉列表..调试器中的这个后面显示模型已正确填充，我没有收到任何形式的错误，但下拉列表项目保持不变。

剃刀

<td>@Html.DropDownList("Role", (IEnumerable<SelectListItem>)ViewBag.RoleDDL, new { @class = "SimDDL", onchange = "RoleDDLChange(this)" })</td>
<td>@Html.DropDownList("EmpDDL", (IEnumerable<SelectListItem>)Model.EmpDDL, new { @class = "SimDDL" })</td>

的jQuery

function RoleDDLChange(id) {
    var SelectedRole = $('#Role').find(":selected").val();
    var url = '/Incentive/ImpersonationPopUp';
    $.ajax
        ({
            data: {
                'DDLSelection': SelectedRole
            },
            type: "get",
            dataType: 'json',
            url: url,
            //crossDomain: true,
            success: function (data) {
                $("#ImpDiaglog").load(data);
            }
        });
}

控制器

public ActionResult ImpersonationPopUp(string DDLSelection = "")
    {
        using (AppDataEntities IP = new AppDataEntities())
        {

            var Roles = IP.IncentivePayGroups.ToList()

            .Select(r => new
            {
                r.role,
                r.PayGroupID
            });
            if (String.IsNullOrEmpty(DDLSelection))
            {
                var Emps = IP.Employees.ToList()
                .Where(E => E.IncentivePayGroup == "2" && E.UltiproActiveInactive != "Terminated" && E.UltiproActiveInactive != "Inactive")
                .Select(e => new
                {
                    e.UltiproEmployeeNo,
                    Name = e.FirstName + " " + e.LastName
                }).OrderBy(e => e.Name);
                SelectList EmpDDL = new SelectList(Emps, "UltiproEmployeeNo", "Name");
                ImpersonationPopUp DDL = new ImpersonationPopUp(EmpDDL);
                ViewBag.RoleDDL = new SelectList(Roles, "PayGroupID", "Role");
                return PartialView(DDL);
            }
            else
            {
                var Emps = IP.Employees.ToList()
                .Where(E => E.IncentivePayGroup == DDLSelection && E.UltiproActiveInactive != "Terminated" && E.UltiproActiveInactive != "Inactive")
                .Select(e => new
                {
                    e.UltiproEmployeeNo,
                    Name = e.FirstName + " " + e.LastName
                }).OrderBy(e => e.Name);
                SelectList EmpDDL = new SelectList(Emps, "UltiproEmployeeNo", "Name");
                ImpersonationPopUp DDL = new ImpersonationPopUp(EmpDDL);
                ViewBag.RoleDDL = new SelectList(Roles, "PayGroupID", "Role");
                return PartialView(DDL);
            }
        }
        return PartialView("~/Incentive/ImpersonationPopUp");
    }

模型

public class ImpersonationPopUp
{
    public SelectList EmpDDL {get; set;}

    public ImpersonationPopUp(SelectList EmpDDL)
    {
        this.EmpDDL = EmpDDL;
    }
}