Details View is displaying “System.Data.Entity.DynamicProxies - asp.net-mvc-4

Question

I dont know how to solve the proble, something is wrong, please help!
the problem is:
The model item passed into the dictionary is of type 'System.Data.Entity.DynamicProxies.Student_0C394DD28745C7061A0EB9964A9FAD1A77E5EB1B24F61D61E2229472BCC850EE', but this dictionary requires a model item of type 'ContosoUniversity.ViewModels.DetailsViewModel'.
StudentController:
public ActionResult Details(int? id)
{
if (id == null)
{
return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
}
Student student = _db.Students.Include(m => m.Comments).SingleOrDefault(x => x.ID == id);
if (student == null)
{
return HttpNotFound();
}
var model = new DetailsViewModel
{
Comment = new Comment(),
Student = student,
Comments = student.Comments.OrderBy(c => c.Id).ToList()
};
return View(student);
}
View:
#model ContosoUniversity.ViewModels.DetailsViewModel
#{
ViewBag.Title = "Details";
}
<h2>Details</h2>
<div>
<h4>Student</h4>
<hr />
<dl class="dl-horizontal">
<dt>
#Html.DisplayNameFor(model => model.Student.LastName)
</dt>
<dd>
#Html.DisplayFor(model => model.Student.LastName)
</dd>
<dt>
#Html.DisplayNameFor(model => model.Student.FirstMidName)
</dt>
<dd>
#Html.DisplayFor(model => model.Student.FirstMidName)
</dd>
<dt>
#Html.DisplayNameFor(model => model.Student.EnrollmentDate)
</dt>
<dd>
#Html.DisplayFor(model => model.Student.EnrollmentDate)
</dd>
<dt>
#Html.DisplayNameFor(model => model.Student.Enrollments)
</dt>
<dd>
<table class="table">
<tr>
<th>Course Title</th>
<th>Grade</th>
</tr>
#foreach (var item in Model.Enrollments)
{
<tr>
<td>
#Html.DisplayFor(modelItem => item.Course.Title)
</td>
<td>
#Html.DisplayFor(modelItem => item.Grade)
</td>
</tr>
}
</table>
</dd>
</dl>
<div class="form-horizontal">
<h4>Movie</h4>
<hr />
#Html.ValidationSummary(true)
<input type="hidden" value="#Model.Comment.Id" name="commentId" />
<div class="form-group">
#Html.LabelFor(model => model.Comment.Name, htmlAttributes: new { #class = "control-label col-md-2" })
<div class="col-md-10">
#Html.EditorFor(model => model.Comment.Name)
#Html.ValidationMessageFor(model => model.Comment.Name)
</div>
</div>
#Html.ValidationSummary(true)
<div class="form-group">
#Html.LabelFor(model => model.Comment.Email, htmlAttributes: new { #class = "control-label col-md-2" })
<div class="col-md-10">
#Html.EditorFor(model => model.Comment.Email)
#Html.ValidationMessageFor(model => model.Comment.Email)
</div>
</div>
#Html.ValidationSummary(true)
<div class="form-group">
#Html.LabelFor(model => model.Comment.Text, htmlAttributes: new { #class = "control-label col-md-2" })
<div class="col-md-10">
#Html.EditorFor(model => model.Comment.Text)
#Html.ValidationMessageFor(model => model.Comment.Text)
</div>
</div>
<div class="form-group">
<div class="col-md-offset-2 col-md-10">
<input type="submit" value="Create" class="btn btn-default" />
</div>
</div>
</div>
}
<div id="comments">
#foreach (var c in Model.Comments)
{
#Html.Partial("_Comment", c)
}
</div>
</div>
<p>
#Html.ActionLink("Edit", "Edit", new { id = Model.Student.ID }) |
#Html.ActionLink("Back to List", "Index")
</p>
DetailsViewModel:
public Student Student { get; set; }
public List<Comment> Comments { get; set; }
public Comment Comment { get; set; }
public virtual ICollection<Enrollment> Enrollments { get; set; }
Comment model:
public int Id { get; set; }
public int CommentId { get; set; }
public Student Student { get; set; }
[Required]
public string Name { get; set; }
[EmailAddress]
public string Email { get; set; }
[Required]
public string Text { get; set; }
Student Model:
public int ID { get; set; }
public string LastName { get; set; }
public string FirstMidName { get; set; }
public DateTime EnrollmentDate { get; set; }
public string FullName
{
get
{
return string.Join(" ", FirstMidName, LastName);
}
}
public virtual ICollection<Enrollment> Enrollments { get; set; }
public List<Comment> Comments { get; set; }
if somebody didnt understand Im trying add commentaries list at Details page with partial view.

Answer 1

You are trying to pass a Student Object to the View where you defined waht object it will handle Namely: #model ContosoUniversity.ViewModels.DetailsViewModel
You need to either in your controller pass the view a DetailsViewModel or you have to rethink what you are doing/ need to do, and make the view handle object Student.
i dont know where this model is but something like:
#model ContosoUniversity.Models.Student

Answer 2

Assuming you have a DisplayTemplates folder in your Shared Views folder named _Comment.cshtml (i.e. a path like /Views/Shared/DisplayTemplates/_Comment.cshtml) you should try the following:
Rename _Comment.cshtml to Comment.cshtml
Replace the following:
<div id="comments">
#foreach (var c in Model.Comments)
{
#Html.Partial("_Comment", c)
}
</div>
with the following:
#Html.DisplayFor(model => model.Comments)
I just fought with this myself and the underscore in the filename was what was breaking things.