Collections are not correctly model-bound

I retrieve an list of items with the action below

    public IActionResult Edit(int id)
    {
        ObservationRepository _obsRepo = new ObservationRepository(_db);
        List<Observation> allMsg = null;
        allMsg = _obsRepo.getObservations(id);
        ViewBag.ModeEdit = true;
        return PartialView("_Observations", allMsg);
    }

The model's view is defined as @model List<Mediagral.Core.Models.Observation>

there an example of input generated for a property with an attribut name that contain an indexed array without name.

[dougbu]

@branciat am I correct the partial view named _Observations.cshtml contains something like the following?

@using System.Collections
@model List
...
@Html.EditorFor(m => m)

If so you may get better results using @model List<Observation> instead. In any case please provide the view and detail the unexpected results.

[danroth27]

@branciat Could you please share exactly what your cshtml view looks like and also the Mediagral.Core.Models.Observation type so that we can try to reproduce the issue? Thanks!

The partial view

@model List<Mediagral.Core.Models.Observation>

<div class="portlet box green">
    <div class="portlet-title">
        <div class="caption">
            <i class="fa fa-edit"></i>Observations
        </div>
        <div class="tools">
            <a class="btn red" href="@Url.RouteUrl("CoreApi", new { area = "Core", controller = "Observation", action = "Create", id = Model.First().AddressableId })" data-ajax="true" data-ajax-mode="after"
               data-ajax-update="#obs_table tbody" style="height:30px">
                <i class="fa fa-plus"></i>
            </a>
        </div>
    </div>
    <div class="portlet-body form">
        @if (ViewBag.ModeEdit)
        {
            Html.BeginForm(FormMethod.Post, new { data_ajax = "true", data_ajax_mode = "replace", data_ajax_update = "#AjaxContent" });
        }
                <div class="form-body">
                    <div class="table-scrollable no-footer">
                        <table aria-describedby="obs_info" role="grid" class="table table-condensed table-hover table-bordered no-footer" id="obs_table">
                            <thead>
                                <tr role="row">
                                    <th>Contenu</th>
                                    <th>Date</th>
                                    <th>Créé par</th>
                                    <th>Actions</th>
                                </tr>
                            </thead>
                            <tbody>
                                @for (int i = 0; i < Model.Count; i++) { 
                                    <tr class="@((i % 2) == 0 ? "even" : "odd" )" role="row">
                                        @if (ViewBag.ModeEdit)
                                        {
                                            <td>
                                                @Html.AntiForgeryToken()
                                                @Html.EditorFor(m => m[i].Content, new { HtmlAttributes = new { @class = "form-control" } })
                                            </td>
                                            <td>
                                                @Html.HiddenFor(m => m[i].AddressableId)
                                                @Html.EditorFor(m => m[i].Created, new { HtmlAttributes = new { @class = "form-control" } })
                                            </td>
                                            <td>
                                                @Html.HiddenFor(m => m[i].Id)
                                                @Html.EditorFor(m => m[i].CreatedBy.UserName, new { HtmlAttributes = new { @class = "form-control" } })
                                            </td>
                                        }
                                        else
                                        {
                                            <td>@Html.DisplayFor(m => m[i].Content)</td>
                                            <td>@Html.DisplayFor(m => m[i].Created)</td>
                                            <td>@Html.DisplayFor(m => m[i].CreatedBy.UserName)</td>
                                        }
                                        <td>
                                            <a class="btn default btn-sm purple" href="@Url.RouteUrl("CoreApi", new { area = "Core", controller = "Observation", action = "Delete", id = Model[i].Id })" data-ajax="true">
                                                <i class="fa fa-trash-o"></i> Supprimer
                                            </a>
                                        </td>
                                    </tr>
                                }
                            </tbody>
                        </table>
                    </div>
                </div>
                <div class="form-actions">
                    <div class="row">
                        <div class="col-md-6">
                            <div class="row">
                                <div class="col-md-offset-3 col-md-9">
                                    @if (ViewBag.ModeEdit)
                                    {
                                        <button type="submit" class="btn green" data-ajax="true" data-ajax-mode="replace" data-ajax-update="#AjaxContent">
                                            <i class="fa fa-pencil"></i> Valider
                                        </button>
                                        <button type="reset" class="btn yellow" data-ajax="true" data-ajax-mode="replace" data-ajax-update="#AjaxContent">
                                            <i class="fa fa-pencil"></i> Annuler
                                        </button>
                                    }
                                    else
                                    {
                                        <a href="@Url.RouteUrl("CoreApi", new { area = "Core", controller = "Observation", action = "Edit", id = Model.First().AddressableId })" class="btn green"
                                           data-ajax="true" data-ajax-mode="replace" data-ajax-update="#AjaxContent">
                                            <i class="fa fa-pencil"></i> Editer
                                        </a>
                                    }
                                </div>
                            </div>
                        </div>
                    </div>
                </div>
        @if(ViewBag.ModeEdit)
        {
            Html.EndForm();
        }
    </div>
</div>

The entity

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;
using Mediagral.User.Models;

namespace Mediagral.Core.Models
{
    public partial class Observation
    {
        public int Id { get; set; }

        public string CreatedById { get; set; }

        public int AddressableId { get; set; }

        [Required, DataType(DataType.Text)]
        public string Content { get; set; }

        [Column(TypeName = "datetime2")]
        public DateTime Created { get; set; }

        public virtual MediagralUser CreatedBy { get; set; }
        public Addressable Addressable { get; set; }
    }
}

[dougbu]

@branciat which part of the generated HTML is not what you expect? anything similarly unexpected in the HTML generated when !ViewBag.ModeEdit?

[danroth27]

@dougbu Presumably the name attribute is empty - we should try to reproduce this. Could you please try it out? Thanks!

@dougbu
I'm at home, i live in france. I try the negation after update my config is the same at work.
i'm missing the database migration scripts for complete installation. I will see monday, back to work.

@dougbu
This don't change anything. I've still the attribute name empty

<input class="form-control text-box single-line" data-val="true" data-val-required="Le champ Content est requis." id="z0__Content" name="[0].Content" value="Le lundi 5 septembre 2011 13:34:55" type="text">

[dougbu]

@branciat did you edit the HTML slightly? everything looks as I'd expect except it should be a self-closing tag e.g. <input ... />.

and what in particular is empty?

Yes i forgot the tag </input> in example, no override editor template, i have the same problem with other partial view and other entity, always a collection as model.
I use visual studio 2015 ctp6 and asp mvc master beta 3.

[dougbu]

the name attribute has value "[0].Content" in the sample you provided. what is the problem?

Yes it's the problem for each view with a collection as model.
The problem is to action level, the [FromForm] don't hydrate the entity when the name is empty.

[HttpPost]
        public IActionResult Edit([FromForm]List<Observation> id)
        {
            ObservationRepository _obsRepo = new ObservationRepository(_db);
            if (id != null && ModelState.IsValid)
            {
                foreach (Observation obs in id)
                {
                    _obsRepo.UpdateObservation(obs);
                }
                return Edit(id[0].AddressableId);
            }
            else
            {
                return PartialView("_Common", id);
            }
        }

I tried with Observation[], the parameter is always null.

I add "id" in the name of the html generated with the web development toolbox of firefox, no problem, the FromForm hydrate the entity.