C# 对表进行排序/搜索不起作用

排序和搜索机制在我们的.NETMVC项目中不起作用。 我完成了控制器和视图的编码，除了排序和搜索之外，一切都很好

控制器：

  public ActionResult Index(string sortOrder, string searchString)
    {
        ViewBag.NameSortParm = String.IsNullOrEmpty(sortOrder) ? "name_desc" : "";
        ViewBag.CustomerNameSortParm = String.IsNullOrEmpty(sortOrder) ? "cust_name_desc" : "";
        ViewBag.LastSucceedOnSortParm = sortOrder == "Date" ? "succeed_date_desc" : "Date";

        var farms = from f in db.Farms
                    select f;

        if (!String.IsNullOrEmpty(searchString))
        {
            farms = farms.Where(s => s.LicenseKey.ToUpper().Contains(searchString.ToUpper()) || s.Name.ToUpper().Contains(searchString.ToUpper()));
        }

        switch (sortOrder)
        {
            case "name_desc":
                farms = farms.OrderByDescending(f => f.Name);
                break;
            case "cust_name_desc":
                farms = farms.OrderByDescending(f => f.CustomerName);
                break;
            case "succeed_date_desc":
                farms = farms.OrderBy(f => f.LastSucceedOn);
                break;
        }

        return View(db.Farms.ToList());
    }

@using (Html.BeginForm())
{
    <p>
        Search: @Html.TextBox("SearchString")
        <input type="submit" value="Search" />
    </p>
}

<table class="table">
    <tr>
        <th>
            @Html.DisplayNameFor(model => model.LicenseKey)
        </th>
        <th>
            @*@Html.DisplayNameFor(model => model.Name)*@
        @Html.ActionLink("Name", "Index", new { sortOrder = ViewBag.NameSortParm })
        </th>
        <th>
            @*@Html.DisplayNameFor(model => model.CustomerName)*@
            @Html.ActionLink("CustomerName", "Index", new { sortOrder = ViewBag.CustomerNameSortParm })
        </th>
        <th>
            @Html.DisplayNameFor(model => model.FarmDate)
        </th>
        <th>
            @*@Html.DisplayNameFor(model => model.LastSucceedOn)*@
            @Html.ActionLink("LastSucceedOn", "Index", new { sortOrder = ViewBag.LastSucceedOnSortParm })
        </th>

        <th></th>
        <th></th>
    </tr>

@foreach (var item in Model) {
    <tr>
        <td>
            @Html.ActionLink(item.LicenseKey, "FarmDetails", "Farm", new { id = item.Id }, null)
        </td>
        <td>
            @Html.DisplayFor(modelItem => item.Name)
        </td>
        <td>
            @Html.DisplayFor(modelItem => item.CustomerName)
        </td>
        <td>
            @Html.DisplayFor(modelItem => item.FarmDate)
        </td>
        <td>
            @Html.DisplayFor(modelItem => item.LastSucceedOn)
        </td>
        <td>
            @Html.ActionLink("Edit", "Edit", new { id=item.Id })
        </td>
        <td>
            @Html.ActionLink("Settings", "Index", "Settings")
        </td>
    </tr>
}

</table>

查看：

  public ActionResult Index(string sortOrder, string searchString)
    {
        ViewBag.NameSortParm = String.IsNullOrEmpty(sortOrder) ? "name_desc" : "";
        ViewBag.CustomerNameSortParm = String.IsNullOrEmpty(sortOrder) ? "cust_name_desc" : "";
        ViewBag.LastSucceedOnSortParm = sortOrder == "Date" ? "succeed_date_desc" : "Date";

        var farms = from f in db.Farms
                    select f;

        if (!String.IsNullOrEmpty(searchString))
        {
            farms = farms.Where(s => s.LicenseKey.ToUpper().Contains(searchString.ToUpper()) || s.Name.ToUpper().Contains(searchString.ToUpper()));
        }

        switch (sortOrder)
        {
            case "name_desc":
                farms = farms.OrderByDescending(f => f.Name);
                break;
            case "cust_name_desc":
                farms = farms.OrderByDescending(f => f.CustomerName);
                break;
            case "succeed_date_desc":
                farms = farms.OrderBy(f => f.LastSucceedOn);
                break;
        }

        return View(db.Farms.ToList());
    }

@using (Html.BeginForm())
{
    <p>
        Search: @Html.TextBox("SearchString")
        <input type="submit" value="Search" />
    </p>
}

<table class="table">
    <tr>
        <th>
            @Html.DisplayNameFor(model => model.LicenseKey)
        </th>
        <th>
            @*@Html.DisplayNameFor(model => model.Name)*@
        @Html.ActionLink("Name", "Index", new { sortOrder = ViewBag.NameSortParm })
        </th>
        <th>
            @*@Html.DisplayNameFor(model => model.CustomerName)*@
            @Html.ActionLink("CustomerName", "Index", new { sortOrder = ViewBag.CustomerNameSortParm })
        </th>
        <th>
            @Html.DisplayNameFor(model => model.FarmDate)
        </th>
        <th>
            @*@Html.DisplayNameFor(model => model.LastSucceedOn)*@
            @Html.ActionLink("LastSucceedOn", "Index", new { sortOrder = ViewBag.LastSucceedOnSortParm })
        </th>

        <th></th>
        <th></th>
    </tr>

@foreach (var item in Model) {
    <tr>
        <td>
            @Html.ActionLink(item.LicenseKey, "FarmDetails", "Farm", new { id = item.Id }, null)
        </td>
        <td>
            @Html.DisplayFor(modelItem => item.Name)
        </td>
        <td>
            @Html.DisplayFor(modelItem => item.CustomerName)
        </td>
        <td>
            @Html.DisplayFor(modelItem => item.FarmDate)
        </td>
        <td>
            @Html.DisplayFor(modelItem => item.LastSucceedOn)
        </td>
        <td>
            @Html.ActionLink("Edit", "Edit", new { id=item.Id })
        </td>
        <td>
            @Html.ActionLink("Settings", "Index", "Settings")
        </td>
    </tr>
}

</table>

@使用（Html.BeginForm（））
{

搜索：@Html.TextBox（“搜索字符串”）

}
@DisplayNameFor（model=>model.LicenseKey）
@*@DisplayNameFor（model=>model.Name）*@
@ActionLink（“Name”，“Index”，new{sortOrder=ViewBag.NameSortParm}）
@*@DisplayNameFor（model=>model.CustomerName）*@
@ActionLink（“CustomerName”，“Index”，new{sortOrder=ViewBag.CustomerNameSortParm}）
@Html.DisplayNameFor（model=>model.FarmDate）
@*@DisplayNameFor（model=>model.LastSucceedOn）*@
@ActionLink（“LastSucceedOn”，“Index”，new{sortOrder=ViewBag.LastSucceedOnSortParm}）
@foreach（模型中的var项目）{
@ActionLink（item.LicenseKey，“FarmDetails”，“Farm”，new{id=item.id}，null）
@DisplayFor（modelItem=>item.Name）
@DisplayFor（modelItem=>item.CustomerName）
@DisplayFor（modelItem=>item.FarmDate）
@DisplayFor（modelItem=>item.LastSucceedOn）
@ActionLink（“编辑”，“编辑”，新的{id=item.id}）
@ActionLink（“设置”、“索引”、“设置”）
}

我的代码哪部分是错的？一定有个简单的错误，但我看不出来。

---

谢谢。

我理解db。农场是完整的列表。您可以对该列表进行排序和筛选，并将结果保存在本地农场变量中。但将未过滤的db.Farms返回给客户端。只需将其替换为农场，它就可以工作了

return View(farms.ToList());

---

执行所有排序，然后忽略所有排序，通过执行返回视图（db.Farms.ToList（））再次调用数据库-它需要

返回视图（farms.ToList（））啊。我知道我犯了一个愚蠢的错误。谢谢你展示。