相关疑难解决方法(0)

我有两个下拉列表.第一个选定的值加载另一个.当我在控制器中有辅助方法时,我该怎么做？

@using (Html.BeginForm())
{
<div>
    <table width="100%" cellpadding="0" cellspacing="0">
        <tr>
            <td><b>Select a District:</b></td>
            <td>@Html.DropDownListFor(m => m.DistrictId, ViewData["DMManagers"] as IEnumerable<SelectListItem>, "Select One")</td>
        </tr>
        <tr>
            <td><b>Select a TM:</b></td>
            <td>@Html.DropDownListFor(m => m.TMId, ViewData["TMManagers"] as IEnumerable<SelectListItem>, "Select One")</td>
        </tr>
    </table>
</div>
}

private void LoadDistrictManagers()
{
    var _DMS = (from c in SessionHandler.CurrentContext.ChannelGroups
                join cgt in SessionHandler.CurrentContext.ChannelGroupTypes on c.ChannelGroupTypeId equals cgt.ChannelGroupTypeId
                where cgt.Name == "District Manager"
                select new { c.ChannelGroupId, c.Name }).OrderBy(m => m.Name);
    ViewData["DMManagers"] = new SelectList(_DMS, "ChannelGroupId", "Name");
}

private void LoadTerritoryManagers(int …