Debugging code in a view (asp.net mvc2)
How do I debug code in the View in asp.net mvc2 application?
Edit after progress last night:
Ok so now I have the following:
in Shared\EditorTemplates\Equipment.ascx
:
<%@ Control Language="C#" Inherits="System.Web.Mvc.ViewUserControl<DAT.Models.Item>" %>
<% using (Html.BeginForm()) {%>
<%: Html.ValidationSummary(true) %>
<div class="editor-label">
<%: Html.Label("Item ID") %>
<%: Html.TextBoxFor(model => model.ItemID) %>
<%: Html.ValidationMessageFor(model => model.ItemID) %>
</div>
<div class="editor-label">
<%: Html.LabelFor(model => model.ModelID) %>
<%: Html.DropDownListFor(x => x.Model.Model1, new SelectList(Model.Model.Model1, "ModelId", "Model", Model.ModelID)) %>
<%: Html.ValidationMessageFor(model => model.ModelID) %>
</div>
...
in Item\Edit.aspx
:
<%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/Site.Master" Inherits="System.Web.Mvc.ViewPage<DAT.ViewModels.ItemEditViewModel>" %>
<% using (Html.BeginForm()) {%>
<%: Html.ValidationSummary(true) %>
<fieldset>
<legend>Fields</legend>
<%: Html.EditorFor(model => model.Item) %>
<p>
<input type="submit" value="Save" />
</p>
</fieldset>
The controller:
public ActionResult Edit(int id)
{
var models = from p in database.Models.Where(x => x.Model1 != null) select p;
var viewModel = new ViewModel
{
Things = database.Things.Single(a => a.ItemID == 开发者_Python百科id),
//tried this:
//Models = database.Models
Models = models
};
return View(viewModel);
}
So I am sure that the problem is with this line
<%: Html.DropDownListFor(x => x.Model.Model1, new SelectList(Model.Model.Model1, "ModelId", "Model", Model.ModelID)) %>
When generating the selectlist, I don't have IEnumerable for the first parameter? Or one of the values I am feeding this is causing null. How do I get the list of models in my view?
EDIT AFTER PULLING ALL MY HAIR OUT:
It seems the problem lies in this example: http://www.asp.net/mvc/tutorials/mvc-music-store-part-4 . Strangely, I am not sure if it is following best practice. Look at the code and how they pass the models about - it seems stupidly obscure using ViewData["Blah"] and the Models as well, why can't you just have it all sent as the model? Look at the code how they have done it:
Album.ascx :
<%@ Import Namespace="MvcMusicStore"%>
<%@ Control Language="C#" Inherits="System.Web.Mvc.ViewUserControl<MvcMusicStore.Models.Album>" %>
<script src="/Scripts/MicrosoftAjax.js" type="text/javascript"></script>
<script src="/Scripts/MicrosoftMvcAjax.js" type="text/javascript"></script>
<script src="/Scripts/MicrosoftMvcValidation.js" type="text/javascript"></script>
<p>
<%: Html.LabelFor(model => model.Title)%>
<%: Html.TextBoxFor(model => model.Title)%>
<%: Html.ValidationMessageFor(model => model.Title)%>
</p>
<p>
<%: Html.LabelFor(model => model.Price)%>
<%: Html.TextBoxFor(model => model.Price)%>
<%: Html.ValidationMessageFor(model => model.Price)%>
</p>
<p>
<%: Html.LabelFor(model => model.AlbumArtUrl)%>
<%: Html.TextBoxFor(model => model.AlbumArtUrl)%>
<%: Html.ValidationMessageFor(model => model.AlbumArtUrl)%>
</p>
<p>
<%: Html.LabelFor(model => model.Artist)%>
<%: Html.DropDownList("ArtistId", new SelectList(ViewData["Artists"] as IEnumerable, "ArtistId", "Name", Model.ArtistId))%>
</p>
<p>
<%: Html.LabelFor(model => model.Genre)%>
<%: Html.DropDownList("GenreId", new SelectList(ViewData["Genres"] as IEnumerable, "GenreId", "Name", Model.GenreId))%>
</p>
View:
<%@ Page Language="C#" MasterPageFile="~/Views/Shared/Site.Master" Inherits="System.Web.Mvc.ViewPage<MvcMusicStore.ViewModels.StoreManagerViewModel>" %>
<asp:Content ID="Content1" ContentPlaceHolderID="TitleContent" runat="server">
Edit - <%: Model.Album.Title %>
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server">
<h2>Edit Album</h2>
<% Html.EnableClientValidation(); %>
<% using (Html.BeginForm()) {%>
<fieldset>
<legend>Edit Album</legend>
<%: Html.EditorFor(model => model.Album, new { Artists = Model.Artists, Genres = Model.Genres}) %>
<p>
<input type="submit" value="Save" />
</p>
</fieldset>
<% } %>
<div>
<%:Html.ActionLink("Back to Albums", "Index") %>
</div>
</asp:Content>
View Model:
using System.Collections.Generic;
using MvcMusicStore.Models;
namespace MvcMusicStore.ViewModels
{
public class StoreManagerViewModel
{
public Album Album { get; set; }
public List<Artist> Artists { get; set; }
public List<Genre> Genres { get; set; }
}
}
And the controller:
//
// GET: /StoreManager/Edit/5
public ActionResult Edit(int id)
{
var viewModel = new StoreManagerViewModel
{
Album = storeDB.Albums.Single(a => a.AlbumId == id),
Genres = storeDB.Genres.ToList(),
Artists = storeDB.Artists.ToList()
};
return View(viewModel);
}
So it looks to me like the model is built in the controller as makes logical sense to me. Then in the view they use this statement which causes my confusion:
<%: Html.EditorFor(model => model.Album, new { Artists = Model.Artists, Genres = Model.Genres}) %>
The model is being split/changed and now we send the other (Artists, Genres) as ViewData ?? Can someone explain, and is this at all fitting with the entire design pattern?
You could put a breakpoint in your controller action and analyze your model and view data.
This being said, why are you using a strongly typed view and ViewData
at the same time? Make sure that ViewData["Models"] as IEnumerable
is not null (in your controller) or even better get rid of it and put it in your model as a strongly typed property. Also I would recommend you using the strongly typed helper DropDownListFor
:
<%: Html.DropDownListFor(
x => x.ModelID,
new SelectList(Model.Models, "ModelId", "Model", Model.ModelID)
)%>
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