ASP.NET MVC； IEnumerable的 <Model>

Question

I have built a small MailApplication for my developing class, it is a homework assignment, but I can't seem to solve this error. I generated a new Controller (MailController) based on a model (Mail). Everything is working just fine, the mail is being sent, but when I return View("Index", mailModel); , I receive an error when submitting the url/Mail/Create (POST) form.

The model item passed into the dictionary is of type 'WebApplication1.Models.Mail', but this dictionary requires a model item of type 'System.Collections.Generic.IEnumerable`1[WebApplication1.Models.Mail]'. 

The following is the Create method of MailController:

        [HttpPost]
        [ValidateAntiForgeryToken]
        public ViewResult Create([Bind(Include = "ID,From,To,Subject,Body")] Mail mail, Models.Mail mailModel)
        {
            if (ModelState.IsValid)
            {
                //Create mail
                MailMessage message = new MailMessage();
                message.To.Add(mailModel.To);
                message.From = new MailAddress(mailModel.From);
                message.Subject = mailModel.Subject;
                message.Body = mailModel.Body;
                message.IsBodyHtml = true;

                //Setup host
                SmtpClient smtp = new SmtpClient();
                smtp.Host = "smtp.gmail.com";
                smtp.Port = 587;
                smtp.UseDefaultCredentials = false;
                smtp.Credentials = new System.Net.NetworkCredential("something@gmail.com", "password!");
                smtp.EnableSsl = true;

                //Send the EMail
                smtp.Send(message);

                return View("Index", mailModel);
            }
            else
            {
                return View(mailModel);
            }
        }

The following is my model:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

namespace WebApplication1.Models
{
    public class Mail
    {
        public int ID { get; set; }
        public string From { get; set; }
        public string To { get; set; }
        public string Subject { get; set; }
        public string Body { get; set; }
    }
}

And the last thing, my view:

@model IEnumerable<WebApplication1.Models.Mail>

@{
    ViewBag.Title = "Index";
}

<h2>Index</h2>

<p>
    @Html.ActionLink("Create New", "Create")
</p>
<table class="table">
    <tr>
        <th>
            @Html.DisplayNameFor(model => model.From)
        </th>
        <th>
            @Html.DisplayNameFor(model => model.To)
        </th>
        <th>
            @Html.DisplayNameFor(model => model.Subject)
        </th>
        <th>
            @Html.DisplayNameFor(model => model.Body)
        </th>
        <th></th>
    </tr>

@foreach (var item in ViewData.Model) {
    <tr>
        <td>
            @Html.DisplayFor(modelItem => item.From)
        </td>
        <td>
            @Html.DisplayFor(modelItem => item.To)
        </td>
        <td>
            @Html.DisplayFor(modelItem => item.Subject)
        </td>
        <td>
            @Html.DisplayFor(modelItem => item.Body)
        </td>
        <td>
            @Html.ActionLink("Edit", "Edit", new { id=item.ID }) |
            @Html.ActionLink("Details", "Details", new { id=item.ID }) |
            @Html.ActionLink("Delete", "Delete", new { id=item.ID })
        </td>
    </tr>
}

</table>

Answer 1

As already pointed out by f0x you model and view are not aligned.

You could either change your view's model definition to:

@model WebApplication1.Models.Mail

Or supply the view with a list from the action.

In here you would need to supply the list:

return View(listOfMailModel);