Foreach 与来自 viewbag 的数据

Question

下面是我的代码。

型号

public class ShiftsModel
{
    public string UID { get; set; }
    public string Date { get; set; }
    public string Time { get; set; }
    public string Location { get; set; }
}

控制器

public class HomeController : Controller
{
    public string xmlPath = HostingEnvironment.MapPath("~/App_Data/data.xml");

    public ActionResult Index()
    {
        XDocument xml = XDocument.Load(xmlPath);

        var shifts = (from b in xml.Descendants("Shift")
                      select new ShiftsModel
                     {
                         UID = (string)b.Attribute("UID"),
                         Date = (string)b.Element("Date"),
                         Time = (string)b.Element("Time"),
                         Location = (string)b.Element("Location")
                     }).ToList();

        return View(shifts);
    }

}

我现在想在我的 Index.cshtml 文件中引用它，如下所示：

@foreach(var shift in (List<object>ViewBag.shifts)) {
<tr>
    <td>
        <input type="text" id="date" name="date" placeholder="Date" value="@(ViewBag.date)" }>
    </td>
    <td>
        <input type="text" id="time" name="time" placeholder="Shift time" value="@(ViewBag.time)" }>
    </td>
    <td>
        <input type="text" id="location" name="location" placeholder="Location" value="@(ViewBag.location)" }>
    </td>
</tr>
}

但是，我在 List<object>ViewBag.shifts 行收到一条错误消息：

Represents a strongly typed list of objects that can be accessed by index.

请问我做错了什么？谢谢:)

Answer 1

据我所知，您只是没有将 collection 传递给控制器中的 ViewBag 查看。

你应该这样传递：

public ActionResult Index()
{
    XDocument xml = XDocument.Load(xmlPath);

    var shifts = (from b in xml.Descendants("Shift")
                  select new ShiftsModel
                 {
                     UID = (string)b.Attribute("UID"),
                     Date = (string)b.Element("Date"),
                     Time = (string)b.Element("Time"),
                     Location = (string)b.Element("Location")
                 }).ToList();
    ViewBag.shifts = shifts; // this line will pass your object
    return View();
}

然后在您的视图中：

    @foreach(var shift in (List<ShiftsModel>ViewBag.shifts)) {
    <tr>
        <td>
            <input type="text" id="date" name="date" placeholder="Date"
                   value="@(shift.Date)" }>
        </td>
        <td>
            <input type="text" id="time" name="time" placeholder="Shift time"
                   value="@(shift.Time)" }>
        </td>
        <td>
            <input type="text" id="location" name="location" placeholder="Location"
                   value="@(shift.Location)" }>
        </td>
    </tr>
    }

但是 MVC 解决问题的方法是像这样使用强类型视图：

控制器：

public ActionResult Index()
{
    XDocument xml = XDocument.Load(xmlPath);

    var shifts = (from b in xml.Descendants("Shift")
                  select new ShiftsModel
                 {
                     UID = (string)b.Attribute("UID"),
                     Date = (string)b.Element("Date"),
                     Time = (string)b.Element("Time"),
                     Location = (string)b.Element("Location")
                 }).ToList();
    ViewData.Model = shifts; // this line will pass your object but now to model
    return View();
}

查看：

@model List<ShiftsModel> @*this is where your model is defined on view*@


@for(int i = 0; i < Model.Count(); i++) {
<tr>
    <td>
        @Html.TextBoxFor(x=> Model[i].Date, new { placeholder = "Date" })
    </td>
    <td>
        @Html.TextBoxFor(x=> Model[i].Time, new { placeholder = "Shift time" })
    </td>
    <td>
        @Html.TextBoxFor(x=> Model[i].Location, new { placeholder = "Location" })
    </td>
</tr>
}

你需要 for 循环而不是 foreach 来解决绑定数组的 MVC 问题，如果你想 post 这个模型到控制器。

Answer 2

正如 teo van kot 指出的那样，您并没有将轮班分配给 viewbag。但将您的 ShiftsModel 作为模型而不是通过 ViewBag 传递会更好，也更合适... 确保您的 Index.cshtml 文件具有以下 using 语句：

@model IEnumerable<ShiftsModel>

如果您像之前那样传递模型：return View(shifts); 那么您可以像这样遍历模型：

@foreach(var shift in Model) 
{
   // do something with your shift
}

Foreach 与来自 viewbag 的数据

Foreach with data from the viewbag

c#

asp.net-mvc

razor

viewbag