c# - 如何将 ViewBag 中的一些对象传递给 Action？ - 保留搜索、排序和分页选项

Question

我有一个显示搜索结果并在分页列表中排序的 View 。我将列标题添加为链接，以使用户能够以这种方式基于列进行排序:

<tr>
    <th>           
        @Html.ActionLink("Reference No", "Index", 
          new { sortOrder = ViewBag.RefNoSortParm, currentFilter = ViewBag.CurrentFilter })
    </th>
    <th>
        @Html.ActionLink("Category", "Index", 
          new { sortOrder = ViewBag.CatSortParm, currentFilter = ViewBag.CurrentFilter })
    </th>
    ... Some other columns
</tr>

我还通过这种方式添加了寻呼机:

Page @(Model.PageCount < Model.PageNumber ? 0 : Model.PageNumber) of @Model.PageCount

@Html.PagedListPager(Model, page => Url.Action("Index",
    new { page, sortOrder = ViewBag.CurrentSort, currentFilter = ViewBag.CurrentFilter }))

我使用的 Action 是这样的:

private Registry_fssEntities db = new Registry_fssEntities();
public ActionResult Index(string sortOrder, SearchTransacModel searchModel, SearchTransacModel currentFilter, int? page)
{            
    var model = from c in db.TRANSACs
                select c;
    ViewBag.CurrentSort = sortOrder;
    ViewBag.DispDateSortParm = String.IsNullOrEmpty(sortOrder) ? "DispDate" : "";
    ViewBag.RefNoSortParm = sortOrder == "RefNo" ? "RefNo_desc" : "RefNo";
    ViewBag.CatSortParm = sortOrder == "Cat" ? "Cat_desc" : "Cat";   
    if (searchModel.DATEDISPFROM != null || searchModel.DATEDISPTO != null || searchModel.DATEDISPFROM != null || searchModel.OFFICERNAME != null || searchModel.APPNAME != null || searchModel.REFNO != null || searchModel.PROCNAME != null)
    {
        page = 1;
    }
    else
    {
        searchModel = currentFilter;
    }
    if (searchModel != null)
    {
        if (!String.IsNullOrEmpty(searchModel.DATEDISPFROM))
        {                    
            ViewBag.DispFrom = searchModel.DATEDISPFROM.ToString();
        }
        else
        {
            searchModel.DATEDISPFROM = "01/01/" + DateTime.Today.Year.ToString();
            ViewBag.DispFrom = "01/01/" + DateTime.Today.Year.ToString();
        }
        if (!String.IsNullOrEmpty(searchModel.DATEDISPTO))
        {                   
            ViewBag.DispTo = searchModel.DATEDISPTO.ToString();
        }
        else
        {
            searchModel.DATEDISPTO = "31/12/" + DateTime.Today.Year.ToString();
            ViewBag.DispTo = "31/12/" + DateTime.Today.Year.ToString();
        }
    }
    if (searchModel != null)
    {
        var tRANSACs = new TransacBusinessLogic();
        model = tRANSACs.GetTransacs(searchModel);

        ViewBag.currentFilter = searchModel;
    }
    List<TransacViewModel> TransactionList = new List<TransacViewModel>();
    foreach (var item in model)
    {
        TransactionList.Add(new TransacViewModel {
                TRANSID = item.TRANSID,
                REFNO = item?.REFNO,
                PROCESS = item?.PROCESS,
                //CATEGORY = item.PROCESS.CATEGORY,
                DOCTYPE = item?.DOCTYPE,
                DATEDEL = returnasdate(item.DATEDEL),
                DATEDISP = returnasdate(item.DATEDISP),
                APPNAME = item?.APPNAME,
                OFFICER = item?.OFFICER,
                DATEREG = item.DATEREG
            });
    }
    switch (sortOrder)
    {
        case "DispDate":
            TransactionList = TransactionList.OrderBy(x => x.DATEDISP).ToList();
            break;
        case "RefNo":
            TransactionList = TransactionList.OrderBy(t => t.REFNO).ToList();
            break;
        case "RefNo_desc":
            TransactionList = TransactionList.OrderByDescending(t => t.PROCESS.CATEGORY.DETAIL).ToList();
            break;
        case "Cat":
            TransactionList = TransactionList.OrderBy(t => t.PROCESS.CATEGORY.DETAIL).ToList();
            break;
        case "Cat_desc":
            TransactionList = TransactionList.OrderByDescending(t => t.REFNO).ToList();
            break;
        default:
            TransactionList = TransactionList.OrderByDescending(t => t.DATEDISP).ToList();
            break;
    }
    int pageSize = 6;
    int pageNumber = (page ?? 1);            
    return View(TransactionList.ToPagedList(pageNumber, pageSize));
}

SearchTransacModel 是一个模型，用于在我将搜索参数传递给 Controller ​​时包含它们。当我通过提交按钮提交搜索表单时它工作正常，我使用 ViewBag 将此搜索条件发送回 View ，如下所示:ViewBag.currentFilter = searchModel;

但是当我单击任何排序操作链接时，我丢失了搜索参数。即，当我到达 Controller 时，currentFilter 为 null。

我将 currentFilter 作为查询字符串传递并为其分配搜索模型，就像在这种情况下一样:

 @Html.ActionLink("Reference No", "Index", new { sortOrder = ViewBag.RefNoSortParm, currentFilter = ViewBag.CurrentFilter })

有人可以帮忙吗？顺便说一句，我是 MVC 的新手。

Answer 1

您不能将 viewbag 中的值传回 Controller 。

相反，您应该在 View 中使用模型绑定(bind)将信息传递给您的 post 方法。