传递到字典中的模型项是"System.Data.Entity.Infrastructure.DbQuery"，但需要"System.Collections.Generic.IEnumerable" [英] The model item passed into the dictionary is 'System.Data.Entity.Infrastructure.DbQuery`, but requires 'System.Collections.Generic.IEnumerable

问题描述

我是MVC的新手，正在尝试建立学生评分系统

i am new to MVC, and trying to build students marks system,

模型类如下:

 public partial class MarksType
 {
    public int MarksTypeId { get; set; }
    public Nullable<int> English { get; set; }
    public Nullable<int> Math { get; set; }
    public Nullable<int> Physics { get; set; }
    public Nullable<int> Chemistry { get; set; }
    public Nullable<int> ComputerScience { get; set; }
    public Nullable<int> MoralScience { get; set; }
    public Nullable<int> TotalMarks { get; set; }
  }

我的控制器如下:

public class MarksController : Controller
{
    MarksEntities marks = new MarksEntities();

public ActionResult MarksProfile()
{
   List<MarksType> yourmarks = from x in marks.MarksType where x.MarksTypeId == 5
                         group x by 1 into y
                         select new MarksType
                         {   

                             English = y.Sum(x => x.English),
                             Math = y.Sum(x => x.Math),
                             Physics = y.Sum(x => x.Physics),
                             Chemistry= y.Sum(x => x.Chemistry),
                             ComputerScience = y.Sum(x => x.ComputerScience),
                             MoralScience= y.Sum(x => x.MoralScience),

                             TotalMarks = y.Sum(x => x.English) + y.Sum(x => x.Math)
                             + y.Sum(x => x.Physics) + y.Sum(x => x. Chemistry)
                             +y.Sum(x => x.ComputerScience) + y.Sum(x => x.MoralScience)
                         }).ToList();



        return View(yourmarks);
    }
}

最后，我的视图看起来像这样:

Finally my View Looks Like this:

@model IEnumerable<MvcMarks.Models.MarksType>

<p>
@Html.ActionLink("Create New", "Create")
</p>
<table>
<tr>
    <th>
        @Html.DisplayNameFor(model => model. MarksTypeId)
    </th>
    <th>
        @Html.DisplayNameFor(model => model.English)
    </th>
    <th>
        @Html.DisplayNameFor(model => model.Math)
    </th>
    <th>
        @Html.DisplayNameFor(model => model.Physics )
    </th>
    <th>
        @Html.DisplayNameFor(model => model.Chemistry)
    </th>
    <th>
        @Html.DisplayNameFor(model => model.ComputerScience)
    </th>
    <th>
        @Html.DisplayNameFor(model => model.MoralScience)
    </th>
    <th></th>
</tr>

@foreach (var item in Model) {
<tr>
    <td>
        @Html.DisplayFor(modelItem => item.MarksTypeId)
    </td>
    <td>
        @Html.DisplayFor(modelItem => item.English)
    </td>
    <td>
        @Html.DisplayFor(modelItem => item.Math)
    </td>
    <td>
        @Html.DisplayFor(modelItem => item.Physics )
    </td>
    <td>
        @Html.DisplayFor(modelItem => item.Chemistry)
    </td>
    <td>
        @Html.DisplayFor(modelItem => item.ComputerScience)
    </td>
    <td>
        @Html.DisplayFor(modelItem => item.MoralScience)
    </td>

    </tr>
    }

    </table>

我收到此错误:

传递到字典中的模型项的类型为'System.Data.Entity.Infrastructure.DbQuery 1[<>f__AnonymousType2 1 [System.Nu> llable 1[System.Int32]]]',but this dictionary requires a model item of type 'System.Collections.Generic.IEnumerable 1 [MvcMarks.Models.MarksType]'".

The model item passed into the dictionary is of type 'System.Data.Entity.Infrastructure.DbQuery1[<>f__AnonymousType21[System.Nu>llable1[System.Int32]]]',but this dictionary requires a model item of type 'System.Collections.Generic.IEnumerable1[MvcMarks.Models.MarksType]'.

我通过右键单击MarksProfile Action Method创建了View，并检查了选中MarksType Model的强类型视图，将脚手架模板选择为List，最后选中了创建为局部视图

i created View by right clicking on MarksProfile Action Method and checked strongly typed view with MarksType Model selected , selected scaffold template to List ,and finally checked create as a partial view

我可以知道我在做什么错

may i know what i am doing wrong

任何帮助都会很棒.

推荐答案

您正在将anonymous type传递给视图，但是它期望使用IEnumerable of MarksType，如下所示:-

You are passing an anonymous type to your view, but it expects an IEnumerable of MarksType, something like this:-

List<MarksType> yourmarks = (from x in marks.MarksType where x.MarksTypeId == 5
                         group x by 1 into y
                         select new MarksType
                         {      
                             MarksTypeId = .. ,
                             English = ..       
                             TotalMarks = y.Sum(x => x.English) +y.Sum(x => x.Math)
                             + y.Sum(x => x.Physics) + y.Sum(x => x. Chemistry)
                             +y.Sum(x => x.ComputerScience) + y.Sum(x => x.MoralScience)
                         }).ToList();

但是，由于您的模型MarksTypeId不包含MarksType的定义，因此您必须将此属性添加到模型中:-

But, since your Model MarksTypeId does not contain a definition of MarksType, you will have to add this property to your model:-

public partial class MarksType
{
    //other properties
    public decimal TotalMarks {get; set; }
}

这篇关于传递到字典中的模型项是"System.Data.Entity.Infrastructure.DbQuery"，但需要"System.Collections.Generic.IEnumerable"的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！