选择列出所选值问题

我有一些代码，第二个有效，第一个无效。这个想法是，用户已经选择了一个网站，然后它显示这个网站的信息，选择一个网站自动提交表单

注意：我不需要第二个，我只是想弄清楚为什么前者不起作用

ViewModel

public class SitesViewModel
{
    public SitesViewModel()
    {
        int allowMaintainSites = SessionWrapper.AllowMaintainSites.HasValue ? SessionWrapper.AllowMaintainSites.Value : 0;
        this.isAllowedMaintain = allowMaintainSites == 1;
    }
    public SelectList companySelectList { get; set; }
    public SelectList siteSelectList { get; set; }
    public SelectList siteSelectList1 { get; set; }
    public SelectList siteTypeSelectList { get; set; }
    public bool isAllowedMaintain { get; set; }
    public bool isAllowedSuper { get; set; }
    public bool companySelected { get; set; }
    public bool siteSelected { get; set; }
    public bool hasSites { get; set; }
    public int? currentSite { get; set; }
    public int? companyId { get; set; }
    public Site site { get; set; }
    public Site site1 { get; set; }
}

控制器：

[HttpGet()]
public ActionResult Sites()
{
    var viewModel = new SitesViewModel();
    viewModel.companySelectList = viewModel.isAllowedMaintain ?
            new SelectList(context.GetCompaniesAll(), "companyId", "name") :
            new SelectList(context.GetCompaniesByUser(SessionWrapper.UserId.Value), "companyId",  "name");
        return View(viewModel);
}
[HttpPost()]
public ActionResult Sites(string data)
{
    var viewModel = new SitesViewModel();
    if (Request["company"] != null)
    {
        int? companyId = stringToNullInt(Request["company"]);
        viewModel.companySelected = true;
        viewModel.companyId = companyId;
        viewModel.companySelectList = viewModel.isAllowedMaintain ?
                new SelectList(context.GetCompaniesAll(), "companyId", "name",companyId) :
                new SelectList(context.GetCompaniesByUser(SessionWrapper.UserId.Value), "companyId", "name",companyId);
        viewModel.siteSelectList = new SelectList(context.GetSitesByCompany(companyId,false),"siteId","name") ;
        viewModel.siteSelectList1 = new SelectList(context.GetSitesByCompany(companyId, false), "siteId", "name");
        viewModel.hasSites = context.GetSitesByCompany(companyId, false).Count() > 0;
        if(!Request["site"] == null)
        {
            int? siteId  = stringToNullInt(Request["site"]);
            viewModel.site = context.GetSiteById(siteId).FirstOrDefault();
            viewModel.siteSelectList = new SelectList(context.GetSitesByCompany(companyId, false), "siteId", "name", viewModel.site.siteId.Value);
        }
        if(!Request["site1"] == null){
            int? siteId  = stringToNullInt(Request["site1"]);
            viewModel.site1 = context.GetSiteById(siteId).FirstOrDefault();
            viewModel.siteSelectList1 = new SelectList(context.GetSitesByCompany(companyId, false), "siteId", "name", viewModel.site1.siteId.Value);
        }
     }
}

查看

@using (Html.BeginForm())
{
    @Html.ValidationSummary(false, "Please fix these errors.");
<div id="CustomerSelect">
    <div class="labels">
            <b class="head">Select Customer</b>
        </div>
        <div class="editors">
    @Html.DropDownList("company", @Model.companySelectList, "Please Select Customer", new Dictionary<string, object> { { "class", "selectList" }, { "onchange", "submit()" } })
        </div>
</div>
    if (Model.companySelected)
    {
        if (!Model.hasSites)
        {
            <div class="result">
                <p>
                    <b class="head">There are no sites found.</b>
                </p>
            </div>
        }
        else
        {
            <div id="SiteSelect">
                <p class="labels">
                    <b class="head">Select Site</b>
                </p>
                <p class="editors">
                   @Html.DropDownList("site",@Model.siteSelectList,"Please Select Site",new Dictionary<string,object>{{"class","selectList"},{"onchange","submit()"}})
                    @Html.DropDownList("site1",@Model.siteSelectList1,"Please Select Site",new Dictionary<string,object>{{"class","selectList"},{"onchange","submit()"}})
                </p>
            </div>
       }
    }
}

现在，当我选择顶部的"site"时，它具有正确的选定值（当我在控制器中调试时），并且correct items属性设置为true。然而，每次加载页面时，它都会选择"请选择站点"。然而，当我更改第二个（"站点1"）时，一切似乎都很好。

有什么建议吗？谢谢

我注意到发生了另一件奇怪的事情，那就是如果我更改里面的代码：

if(!Request["site"]==null){
}

要使用viewModel.site而不是viewModel.site1，它将起作用。。。发生了一些奇怪的事情

编辑：已解决

解决方法是将所有内容更改为不同的名称。我想不知怎么的，当我打电话给时

Html.DropDownList("site",....) 

它试图将它与我的SitesViewModel中的属性、站点相匹配，这不是我想要的！我目前已经将其重命名为"site1"，一切似乎都正常工作，这解释了为什么在上面的代码中，它根本不起作用，然后当我根据Secret Squirrel的回答添加site1属性时，

Html.DropDownList("site1",...) didn't work either!

我希望这能帮助到未来的某个人，因为天哪，这需要很长时间才能解决！

ViewModel.site1
ViewModel.site2

ViewModel.site