Question

我正在尝试使用LINQ查询的结果在MVC应用程序中创建下拉列表。我使用this answer作为参考。但是，当我尝试为我的案例实施时，我收到错误：'System.String' does not contain a property with the name 'SAMPLING_EVENT'

我的代码如下：

控制器

public class HomeController : Controller
{
    //
    // GET: /Home/

    public ActionResult Index()
    {
        ViewBag.Title = "Sample Tracker Tool";
        DateTime nineMonthsAgo = DateTime.Now.AddDays(-270);

        var context = new EDMS_Entities();
        var resultSet = (from samplingEvents in context.EDMS_SAMPLES
                        where samplingEvents.RECORD_CREATED_DATE >= nineMonthsAgo
                        orderby samplingEvents.SAMPLING_EVENT
                        select samplingEvents.SAMPLE_ID)
                        .Distinct();

        var viewModel = new SamplingEventsVM();
        viewModel.SamplingEvents = new SelectList(resultSet, "SAMPLING_EVENT", "SAMPLING_EVENT");

        return View(viewModel);
    }
}

ViewModel类

public class SamplingEventsVM
{
    public int SelectedSamplingEvent { get; set; }
    public SelectList SamplingEvents { get; set; }
}

查看

@model SamplingEventsVM

<h2>@ViewBag.Title</h2>

<span>
    @Html.DropDownListFor(model => model.SelectedSamplingEvent, Model.SamplingEvents, "Sampling Event")
</span>

我做错了什么？

Answer 1

您正在选择此select samplingEvents.SAMPLE_ID

因此，您可能会获得int 的列表，具体取决于您的ID类型

然后，您尝试使用属性值"SAMPLING_EVENT"

创建一个选择列表

在您使用。

填充resultSet的int对象上不存在

而是这样做：

    var resultSet = (from samplingEvents in context.EDMS_SAMPLES
                    where samplingEvents.RECORD_CREATED_DATE >= nineMonthsAgo
                    orderby samplingEvents.SAMPLING_EVENT
                    select samplingEvents)
                    .Distinct();

如何从LINQ查询创建DropDownList

1 个答案: