Getting 404 on a simple controller - asp.net-mvc

Question

I'm creating a simple form to upload a file (which can be given a friendly name).
I've gone over this code time and time again, but always get a 404 when the form posts to /MyEntities/Add (this is a post-only URL on purpose).
Any thoughts would be much appreciated - I simply can't see what I've done wrong.
The controller:
public class MyEntitiesController : Controller
{
private DataFilesComparisonRepository repository = new DataFilesComparisonRepository();
public ActionResult Index()
{
List<MyEntitiesDataset> datasets = repository.GetMyEntitiesDatasets();
return View(datasets);
}
[HttpPost]
public ActionResult Add(HttpPostedFileBase postedFile, string friendlyName)
{
repository.AddMyEntities(friendlyName, postedFile.FileName, postedFile.InputStream);
return RedirectToAction("Index");
}
}
And the view:
<%# Page Language="C#" MasterPageFile="~/Views/Shared/Site.Master" Inherits="System.Web.Mvc.ViewPage<List<MyEntitiesDataset>>" %>
<%# Import Namespace="DataFilesComparison.Models" %>
<asp:Content ID="Content1" ContentPlaceHolderID="TitleContent" runat="server">
The Title
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server">
<% Html.BeginForm("Add", "MyEntities", FormMethod.Post, new { enctype = "multipart/form-data" }); %>
<p>
<input type="file" name="postedFile" />
<label for="friendlyName">Friendly Name:</label>
<%= Html.TextBox("friendlyName") %>
<input type="submit" value="Add" />
</p>
<% Html.EndForm(); %>
<% if (Model == null || Model.Count == 0) { %>
<p>No datasets found.</p>
<% } else { %>
<ul>
<% foreach (MyEntitiesDataset dataset in Model) { %>
<li>
<%= dataset.Name %>
[<%= Html.ActionLink("X", "Delete", new { ID = dataset.ID })%>]
</li>
<% } %>
</ul>
<% } %>
</asp:Content>

Answer 1

The model you are passing into the view is not the same of the same type that you are posting back into the Add() method, which may be confusing the default routing settings. Although I see you have been explicit about which method to call, I have had problems like this before. Maybe try creating a ViewModel with the properties you need for the GET and POST, then using them in both the View and the Controller methods. Like this:
Model
public MyViewModel
{
public List<MyEntitiesDataset> Datasets {get; set;}
public HttpPostedFileBase PostedFile {get; set;}
public string FriendlyName {get; set;}
}
Controller Methods
public ActionResult Index()
{
MyViewModel model = new MyViewModel();
model.Datasets = repository.GetMyEntitiesDatasets();
return View(datasets);
}
[HttpPost]
public ActionResult Add(MyViewModel model)
{
repository.AddMyEntities(model.FriendlyName, Model.PostedFile.FileName, Model.postedFile.InputStream);
return RedirectToAction("Index", model);
}
View
%# Page Language="C#" MasterPageFile="~/Views/Shared/Site.Master" Inherits="System.Web.Mvc.ViewPage<MyViewModel>" %>
<%# Import Namespace="DataFilesComparison.Models" %>
<asp:Content ID="Content1" ContentPlaceHolderID="TitleContent" runat="server">
The Title
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server">
<% Html.BeginForm("Add", "MyEntities", FormMethod.Post, new { enctype = "multipart/form-data" }); %>
<p>
<input type="file" name="postedFile" />
<label for="Model.FriendlyName">Friendly Name:</label>
<%= Html.TextBoxFor(m => m.FriendlyName) %>
<input type="submit" value="Add" />
</p>
<% Html.EndForm(); %>
<% if (Model.Datasets == null || Model.Datasets.Count == 0) { %>
<p>No datasets found.</p>
<% } else { %>
<ul>
<% foreach (var dataset in Model.Datasets) { %>
<li>
<%= dataset.Name %>
[<%= Html.ActionLink("X", "Delete", new { ID = dataset.ID })%>]
</li>
<% } %>
</ul>
<% } %>
</asp:Content>
You might have to play around with the file uploader (not sure if there is an Html.FileFor, but hopefully you get the idea!
Good luck.