Save multiple rows simultaneously from the same fo

I have a table that has one empty column into which user can enter a comment:

Table
-----

TbMapId |        UniqueAdp         |    Dealership    |    Line
--------------------------------------------------------------------
1       |    [Insert comment here] |    Derby         |    abc123
2       |    [Insert comment here] |    Keighley      |    cda345
3       |    [Insert comment here] |    Manchester    |    876ghj

There is a lot of data to comment on, I can't expect a user to open an 'Edit' page and type in a comment one by one. Instead I need user to be able to input a bunch of comments (say 20 at a time against 20 rows) and save them all at one click of submit button.

If you want to jump straight to working solution go to EDIT #2 & look at Rudi's accepted answer

View

        <form asp-action="TbMapViewEdit">
            <div class="col-lg-6">
                <div class="row">
                    <input type="submit" value="Save" class="btn btn-primary" />
                    <div class="col-md-12">
                        <table class="table table-condensed table-bordered table-hover">
                            <thead>
                                <tr>
                                    <td><b>TEMP ID</b></td>
                                    <td><b>Map To</b></td>
                                    <td><b>Accounts Code</b></td>
                                    <td><b>Line</b></td>
                                    <td><b>Map Result</b></td>
                                </tr>
                            </thead>
                            <tbody>

                                @for (int i = 0; i < Model.TBMapBalancesList.Count; i++)
                                { 
                                    <tr>
                                        <td>
                                            @Html.DisplayFor(Model => Model.TBMapBalancesList[i].TbMapId)
                                            @Html.HiddenFor(Model => Model.TBMapBalancesList[i].TbMapId)
                                        </td>
                                        <td>@Html.EditorFor(Model => Model.TBMapBalancesList[i].UniqueAdp, new { @class = "control-label_DI" })</td>
                                        <td>@Html.DisplayFor(Model => Model.TBMapBalancesList[i].AccountsCode)</td>
                                        <td>@Html.DisplayFor(Model => Model.TBMapBalancesList[i].Line)</td>
                                        <td>@Html.DisplayFor(Model => Model.TBMapBalancesList[i].MapResult)</td>
                                    </tr>
                                }

                            </tbody>
                        </table>
                    </div>
                </div>
            </div>
        </form>

Model

I've learned today that I need to use List to be able to iterate through the lines in table by the use of @for loop (as shown above). before I was trying to use IEnumerable. So I added a definition to the model for public List<TBMapBalances> TBMapBalancesList { get; set; }

 public class TbMapViewModel
    {
        public IEnumerable<ASPNET_Core_1_0.Models.TBMapBalances> TBMapBalances { get; set; }
        public IEnumerable<ASPNET_Core_1_0.Models.TBMapUniqueADP> TBMapUniqueADP { get; set; }
        public List<TBMapBalances> TBMapBalancesList { get; set; }

       [...]

    }

Controller:

Now this is where I need the help with, my code doesn't throw any errors at all. When I press Submit nothing happens:

        [Authorize]
        [HttpPost]
        public async Task<IActionResult> TbMapViewEdit(TbMapViewModel tbMapViewModel)
        {

            if (ModelState.IsValid)
            {
                foreach (var TbListId in tbMapViewModel.TBMapBalancesList)
                {
                    var getCode = _context.TBMapBalances.Where(p => p.TbMapId == TbListId.TbMapId).FirstOrDefault();

                    if (getCode != null)
                    {
                        getCode.TbMapId = TbListId.TbMapId;
                    }

                }

                try
                {
                    _context.Update(tbMapViewModel.TBMapBalances);
                    await _context.SaveChangesAsync();
                }

                catch (DbUpdateConcurrencyException)
                {
                    throw;
                }
            }

            return RedirectToAction("TbMapView");
        }

EDIT #1

Changes to View

        <form asp-action="TbMapViewEdit">
            <div class="col-lg-6">
                <div class="row">
                    <input type="submit" value="Save" class="btn btn-primary" />
                    <div class="col-md-12">
                        <table class="table table-condensed table-bordered table-hover">
                            <thead>
                                <tr>
                                    <td><b>TEMP ID</b></td>
                                    <td><b>Map To</b></td>
                                    <td><b>Accounts Code</b></td>
                                    <td><b>Line</b></td>
                                    <td><b>Map Result</b></td>
                                </tr>
                            </thead>
                            <tbody>
                                @for (int i = 0; i < Model.TBMapBalances.Count; i++)
                                { 
                                    <tr>
                                        <td>
                                            @Html.DisplayFor(Model => Model.TBMapBalances[i].TbMapId)
                                            @Html.HiddenFor(Model => Model.TBMapBalances[i].TbMapId)
                                        </td>
                                        <td>@Html.EditorFor(Model => Model.TBMapBalances[i].UniqueAdp, new { @class = "control-label_DI" })</td>
                                        <td>@Html.DisplayFor(Model => Model.TBMapBalances[i].AccountsCode)</td>
                                        <td>@Html.DisplayFor(Model => Model.TBMapBalances[i].Line)</td>
                                        <td>@Html.DisplayFor(Model => Model.TBMapBalances[i].MapResult)</td>
                                    </tr>
                                }

                            </tbody>
                        </table>
                    </div>
                </div>
            </div>
        </form>

Changes to model

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;

namespace ASPNET_Core_1_0.Models.TbMapViewModels
{
    public class TbMapViewModel
    {

        public IEnumerable<ASPNET_Core_1_0.Models.TBMapUniqueADP> TBMapUniqueADP { get; set; }
        public List<TBMapBalances> TBMapBalances { get; set; }

        [...]
    }
}

Changes to Controller:

Now this is where I need the help with, my code doesn't throw any errors at all when at the current state - when I press Submit nothing happens and no data gets saved to the database.

however, when you uncomment line _context.Update(tbMapViewModel.TBMapBalances); I get an error that List is not part of any Model and is not found.

Also, below code is something I wrote trying to follow this SO post: update-multiple-records-at-once-in-asp-net-mvc - Initially I was trying to make it Async but I was getting even more errors and couldn't continue. I thought I am going to follow it as closely as possible in hope that it will get me a working starting point.

        [Authorize]
        [HttpPost]
        public IActionResult TbMapViewEdit(TbMapViewModel tbMapViewModel)
        {

            if (ModelState.IsValid)
            {
                foreach (var TbListId in tbMapViewModel.TBMapBalances)
                {
                    var getCode = _context.TBMapBalances.Where(p => p.TbMapId == TbListId.TbMapId).FirstOrDefault();

                    if (getCode != null)
                    {
                        getCode.TbMapId = TbListId.TbMapId;
                    }

                }
               // _context.Update(tbMapViewModel.TBMapBalances);
                _context.SaveChanges();

            }

            return RedirectToAction("TbMapView");
        }

EDIT #2 - A hero to the rescue - big thanks to @RudiVisser for help

First of all if any of you guys are - like me - stuck using .net core 1.0.0 make sure you upgrade to the latest version first (1.1.7 lts). Part of my grief was that I was an USER 1.0 and did not upgrade my installation as fixes and additions kept coming out. Don't be that guy, like I was...

All below is thanks to Rudi's help:

View

@using (Html.BeginForm("TbMapViewEdit", "TbMap"))
{
            <div class="col-lg-6">
                <div class="row">
                    <input type="submit" value="Save" class="btn btn-primary" />
                    <div class="col-md-12">
                        <table class="table table-condensed table-bordered table-hover">
                            <thead>
                                <tr>
                                    <td><b>TEMP ID</b></td>
                                    <td><b>Map To</b></td>
                                    <td><b>Accounts Code</b></td>
                                    <td><b>Line</b></td>
                                    <td><b>Map Result</b></td>
                                </tr>
                            </thead>
                            <tbody>
                                 @Html.EditorFor(m => m.TBMapBalances);
                            </tbody>
                        </table>
                    </div>
                </div>
            </div>
}

Put your "Method", "Controller" in (Html.BeginForm("TbMapViewEdit", "TbMap")) otherwise the form POST action will be set to the current location.

Model

Truncated for brevity. I have view model with List that I will be saving the data to and one other table just for displaying some info.

 public class TbMapViewModel
    {
        public IEnumerable<ASPNET_Core_1_0.Models.TBMapUniqueADP> TBMapUniqueADP { get; set; }
        public List<TBMapBalances> TBMapBalances { get; set; } = new List<TBMapBalances>();

[...]
}

Controller

[Authorize]
[HttpPost]
public IActionResult TbMapViewEdit(TbMapViewModel tbMapViewModel)
{

    if (ModelState.IsValid)
    {
        foreach (var TbListId in tbMapViewModel.TBMapBalances)
        {
            var getCode = _context.TBMapBalances.Where(p => p.TbMapId == TbListId.TbMapId).FirstOrDefault();

            if (getCode != null)
            {
                getCode.UniqueAdp = TbListId.UniqueAdp;
            }

        }
        _context.SaveChanges();
    }

    return RedirectToAction("TbMapView");
}

Error that I was making here is that I was trying to replace the key with essentially the copy of itself (Find ID of 1 and set it to ID of 1) instead of picking up on the actual one field that I needed to edit which in my case was UniqueAdp.

Then came the new thing to me, which was Editor Template:

Editor Template

Create a folder called EditorTemplates in 'Shared' Folder under your 'Views' folder with the exact name of the model that you intend to edit. In my case the model was called TBMapBalances so I created a TBMapBalances.cshtml file inside the newly created folder, then pasted this (this was originally in my main view file):

@model ASPNET_Core_1_0.Models.TBMapBalances

<tr>
    <td>
        @Html.DisplayFor(Model => Model.TbMapId)
        @Html.HiddenFor(Model => Model.TbMapId)
    </td>
    <td>@Html.EditorFor(Model => Model.UniqueAdp, new { @class = "control-label_DI" })</td>
    <td>@Html.DisplayFor(Model => Model.AccountsCode)</td>
    <td>@Html.DisplayFor(Model => Model.Line)</td>
    <td>@Html.DisplayFor(Model => Model.MapResult)</td>
</tr>

By the way the new { @class = "control-label_DI" } is there to supposedly add class to each created input field. This doesn't seem to work in .net core and is left there just as a reminder to myself that I need to do this somehow.

Research:

Update multiple records at once in asp.net mvc

https://docs.microsoft.com/en-us/aspnet/core/mvc/views/working-with-forms

http://www.binaryintellect.net/articles/b1e0b153-47f4-4b29-8583-958aa22d9284.aspx

How to bind an Array in MVC Core

https://www.red-gate.com/simple-talk/dotnet/asp-net/model-binding-asp-net-core/

ASP.NET Core 1.0 POST IEnumerable<T> to controller

回答1:

This problem has 2 parts to it, the first is that there needed to be a way to edit collections of data. This can be solved with EditorTemplates, which involves creating a single editor model and then calling @Html.EditorFor(..) on the collection of items you wish to edit.

A minimal sample (Full Fx, not Core) is available on Github.

The second problem was with the way the entities were being updated, the property being changed was wrong and hence not saving (the PK was being updated to the PK) and the entity was being attached when it's already tracked.

foreach (var TbListId in tbMapViewModel.TBMapBalancesList)
{
    var getCode = _context.TBMapBalances.Where(p => p.TbMapId == TbListId.TbMapId).FirstOrDefault();
    if (getCode != null)
    {
        getCode.TbMapId = TbListId.TbMapId;
    }
}
try
{
    _context.Update(tbMapViewModel.TBMapBalances);
    await _context.SaveChangesAsync();
}
catch (DbUpdateConcurrencyException)
{
    throw;
}

It's important to remember what Entity Framework does for you when you retrieve a model from the database. It is automatically tracked by the context, and so it's already attached and ready to update, anything you change will be automatically tracked and subsequently saved.

The call to _context.Update(..) tries to attach the non-tracked models (from your POSTed data) to the context based on ID, but because you've already pulled that ID out (in your .Where(..).FirstOrDefault(..)) it's already tracked, and so blows up.

Also given that this is EFC 1.0 and you have no .Find(..) method, using .SingleOrDefault(..) is probably a better method to use on a primary key field.

Your rewritten code could be as so:

foreach (var postedModel in tbMapViewModel.TBMapBalancesList)
{
    var dbModel = _context.TBMapBalances.SingleOrDefault(p => p.TbMapId == postedModel.TbMapId);
    if (dbModel != null)
    {
        dbModel.UniqueAdp = postedModel.UniqueAdp;
    }
}
await _context.SaveChangesAsync();

For posterity though I wouldn't recommend it for security reasons, if you wanted to attach your whole posted model to the context (based on ID) and update it, you can do so with code similar to your original, removing the foreach loop:

_context.UpdateRange(tbMapViewModel.TBMapBalances);
await _context.SaveChangesAsync();

(I don't recommend it because everything that was posted will then be set in the database, from experience it's advisable to only set the fields you're expecting to update as per the first code set. It should, however, be quicker than the foreach loop given that you're not loading from the database and saving back in, only the latter)

回答2:

Do you have the inputs for the comments already built into the razor page? I do not see them. What you would want to do is create a form with the input types that you want for each item in the loop inside the loop. Each form would then reference the iterator as a hidden value to pass when posted. If the loop is foreach(var item in Model.items){} you would have a form containing the inputs in that block with a hidden input that looks like <input type="hidden" name="index" value="@item.index"/> This will allow you to post with whatever identifier you need to attach that specific form data to the correct model.

See this answer for the structure of the form inside the loop Multiple forms on one MVC form, created with a loop, only the first submits data