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Passing back a single object when using EditorFor(model[])

This has been a thorn in my side for a while. If I use EditorFor on an array of objects and the editor Template has a form in it ex.
public class FooController:Controller {
public ActionResult Action(Foo foo) {
// ...
}
}
Index.cshtml
#model IEnumerable<Foo>
#Html.EditorFor(m=> m)
EditorTemplate
#model Foo
#using (Html.BeginForm("action", "controller"))
{
#Html.TextBoxFor(f=> f.A)
#Html.CheckBoxFor(f=> f.B)
#Html.LabelFor(f=> f.B)
}
So I'll hit a few problems.
The checkbox label's for doesn't bind correctly to the checkbox (This has to do with the label not receiving the proper name of the property ([0].A as opposed to A).
I'm aware I can get rid of the pre- text by doing a foreach on the model in Index but that screws up ids and naming as the framework doesnt realize there are multiples of the same item and give them the same names.
For the checkboxes I've just been doing it manually as such.
#Html.CheckBoxFor(m => m.A, new {id= Html.NameFor(m => m.A)})
<label for="#Html.NameFor(m => m.A)">A</label>
However I cant solve the inability of the controller to accept the item as a single model. I've even tried allowing an array of Foo's in the Action parameters but that only work when its the first item being edited ([0]...) if its any other item in the array (ex. [1].A) the controller doesn't know how to parse it. Any help would be appreciated.

Make your model a class with the properties you need.
create a class in your Models subfolder
public class MyModel {
public IEnumerable<Foo> Foolist { get ; set;}
public string Something { get;set;}
}
your EditorFor will have to have a foreach loop for Foolist...
MVC will attempt to put your model together from the form and return it to your POST action in the controller.
Edit:
You could create an EditorTemplate for foo. In Views/Shared/EditorTemplates folder, create FooTemplate.cs
#model Foo
<div class="span6 float-left" style="margin-bottom: 6px">
#Html.TextBoxFor(m => m.A, new { style = "width:190px" })
#Html.CheckBoxFor(m => m.B, new { style = "width:40px" })
#Html.ValidationMessage("foo", null, new { #class = "help-inline" })
</div>
then in your view
#foreach (var myFoo in Model)
{
#EditorFor(myFoo)
}
This still suffers from the "model gets passed back as a whole" requiredment of yours. Not sure about why there is a need to process these individually.

Hah finally solved this - Here's how I did it. As a bit of background HTML forms use the name attribute when submitting forms, but the label for element uses Id . so I only adapt the id tag to have the prefix and not the name tag.
--In the cshtml file
#{
var prefix = ViewData.TemplateInfo.HtmlFieldPrefix;
ViewData.TemplateInfo.HtmlFieldPrefix = "";
}
then I can specify the id for the properties by their prefix while letting the name remain the same like so
#Html.CheckBoxFor(m => m.A,
new {id = prefix+"."+ Html.NameFor(m => m.A)})
<label for="#prefix.#Html.NameFor(m => m.A)">A!</label></div>

Unable to submit List of model in MVC [duplicate]

This question already has answers here:
Post an HTML Table to ADO.NET DataTable
(2 answers)
Closed 7 years ago.
I am displaying a list of items in a Collection in edit mode in a view. after editing the documents, I want to submit. But I am unable to postback the list. List shows null.
here is my View
#model List<NewsLetter.Models.NewsLetterQuestions>
#using (Html.BeginForm("GetAnswersfromUser", "NewsLetter", FormMethod.Post, null))
{
#Html.AntiForgeryToken()
foreach (var item in Model) {
<div>
#Html.DisplayFor(modelItem => item.Question)
</div>
<div>
#Html.TextAreaFor(modelItem => item.Answer)
</div>
}
<div class="form-group">
<div class="col-md-offset-2 col-md-10">
<input type="submit" value="Submit" class="btn btn-default" />
</div>
</div>
}
Here is my Controller
public ActionResult GetAnswersfromUser(string id)
{
id = "56c5afc9afb23c2df08dd2bf";
List<NewsLetterQuestions> questions = new List<NewsLetterQuestions>();
var ques = context.NewsLetterQuestionCollection.Find(Query.EQ("NewsLetterId", id));
foreach(var x in ques)
{
questions.Add(x);
}
return PartialView(questions);
}
[HttpPost]
public ActionResult GetAnswersfromUser(List<NewsLetterQuestions> nql)
{
string id = "56c5afc9afb23c2df08dd2bf";
foreach (var item in nql)
{
var query = Query.And(Query.EQ("NewsLetterId", id), Query.EQ("Question", item.Question));
var update=Update<NewsLetterQuestions>
.Set(r => r.Answer, item.Answer);
context.NewsLetterQuestionCollection.Update(query,update);
}
return RedirectToAction("NewsLetterIndex");
}
When i hit submit it throws error.
System.NullReferenceException: Object reference not set to an instance of an object.
In the line
foreach (var item in nql)
which means that nql is null.

In order for the model binder to be able to bind the posted data, all your input names need to be in the format of [N].Property, where N is the index of the item within the list. In order for Razor to generate the input names properly, then, you need to pass it an indexed item, which means you need a for loop, rather than a foreach:
#for (var i = 0; i < Model.Count(); i++)
{
...
#Html.TextAreaFor(m => m[i].Answer)
...
}

You're never passing the list back to the controller's Post handler. You need to route the list back to the controller.
You should be doing something similar to this untested code :)
Html.BeginForm("Index", "Home", new { #nql=Model }, FormMethod.Post)
Take a look at this post as well. It is similar to your issue: Pass multiple parameters in Html.BeginForm MVC4 controller action and this Pass multiple parameters in Html.BeginForm MVC

Query Selected Items using checkbox in MVC

I like to ask if how would it be possible that the selected items in the checkbox will be used in making linq query in MVC.
I have this one in my view where in I displayed all the possible options in which the user will just simply select the types of softwares that will be used to generate reports.
#using (Ajax.BeginForm("Create_Report", "Softwares",
new AjaxOptions
{
HttpMethod = "POST",
InsertionMode = InsertionMode.Replace,
UpdateTargetId = "target2"
}))
{
#Html.ValidationSummary(true)
<p>For A Reports: Kindly check softwares to create reports.</p><br />
foreach (var item in Model) {
<input type="checkbox" value="#item.software_name" name="software_type"/>#item.software_name
<br />
}
<input type="submit" value="Create Report"/>
}
After that, I want that the selected software types will be used in the query like for example if the user selects Adobe Pro, Adobe Illustrator, MS Visio, and Acrobat, the query should go like "Select from Software _table where software__type = "Adobe Pro" && software_type ="Adobe Illustrator && "so fort.
Is there any ways to shorten the query using the selected items from the checkbox? Any help is much appreciated.

Assuming your POST method is
[HttpPost]
public ActionResult Create_Report(string[] software_type)
then software_type will contain an array of the selected values so you can use .Contains() to filter the query
var items = db.Software.Where(s => software_type.Contains(s.software_type))
Side note: remove those awful underscores from your properties and follow normal naming conventions (SoftwareType, SoftwareName, etc or simply Type, Name etc since they are already in a class named Software)

You need to define a collection to store you selected items and use model binding to map the selected items to this property.
//store checked Items
public IEnumerable<string> SelectedSoftware { get; set; }
//check box list items
public List<string> SoftwareList = new List<string>();
foreach (var item in Model.SoftwareList )
{
<input type="checkbox" name="SelectedSoftware" value="#item">#item
}
in your controller:
public ActionResult Create_Report(string[] SelectedSoftware)
{
//do action
}

How to perform a simple multiple selection in a table ASP.NET MVC4

Here is what my view looks like:
#model Affiliate
<div class="box paint color_16">
<div class="title">
<h4><i class="icon-tasks"></i><span>#Model.CompanyName's Commissions</span> </h4>
</div>
<div class="content top ">
<div class="subtitle">
#Html.ActionLink("Void", "DeleteInvoice", new { commList = "??", affId = Model.Id }, new { #class = "btn" })
#Html.ActionLink("Create Invoice", "CreateInvoice", new { commList = "??", affId = Model.Id }, new { #class = "btn" })
#Html.ActionLink("Pay", "PayInvoice", new { commList = "??", affId = Model.Id }, new { #class = "btn" })
</div>
<table class="table table-striped table-hover">
<tr>
<h3>Commissions</h3>
</tr>
<tr>
<td></td>
<td>Amount</td>
<td>Status</td>
<td>Action</td>
</tr>
#foreach (var item in Model.Commissions)
{
<tr>
#if (item.Status == ViewBag.PaymentStatus || ViewBag.PaymentStatus == "All")
{
<td>#Html.CheckBox("commId", new { value = item.Id })</td>
<td>#Html.DisplayFor(x => item.PayoutAmount)</td>
<td>#Html.DisplayFor(x => item.Status)</td>
}
</tr>
}
</table>
</div>
What I want to be able to do is when I hit an actionlink on the top, grab all the items from the table that are checked, and pass that list of id's to the controller logic. I am assuming a viewmodel may be the solution, something like this:
public Affiliate affilite { get; set; }
public List<int> selectedItems { get; set; }
etc.
But how to I get the selected Items into that VM selectedItems container?

Based off your comments, you don't seem to be looking for the most "correct" answer, but rather just a quick and dirty "how would I do this" answer. If you just want to pass the list, you could setup your controller action like this:
public ActionResult MyAction(int[] id)
{
...
}
Or, you seem to indicate it is strongly typed to a view model with a property that contains a List (I would shorten the name of the property, you'll see why in a second).
In javascript, the easiest thing to do would be to use jQuery to bind a click event on your hyperlink that gets the list of items that are checked and appends that to the query string.
$("#myLink").click(function()
{
var url = "site.com/action?";
var ids = $(".table").find("input:checked");
ids.each(function()
{
url += "id=" + $(this).val() + "&"
});
window.location = url;
});
Basically, you want to create one long query string with the action parameter's name repeated over and over, which identifies an array. It looks something like this (id is for int[] id in MyAction):
id=15&id=20&id=25&id=30&....
And then once the query string is built, redirect the user to that url. MVC should then be able to bind that to an array and you're all set.
That's basically the idea, anyway; the syntax and the javascript I wrote could be way off so don't copy my code and expect it to work as is - I wrote that off the top of my head. If your action is bound to a viewmodel, then you need to set the parameter in the query string to the name of the property of your model:
selectedids=1&selectedids=2&selectedids=3...
Or, if the array is a property of an object, which is a property of the model...
model.selectedids=1&model.selectedids=2&model.selectedids=3...
You'll just need to play around with it some.

Use html checks inside form tag ( you could use helpers too) and post the model to a post action.
MVC will serialize the model automatically

dropdown in mvc3 edit form

This maybe very simple but I cant seem to sort it out on my own.
I have created a simple db and entity modal that looks like this
I am trying to create an Create form that allows me to add a new Order. I have a total of 3 tables so what I am trying to do is have the form allowing the person to enter Order date and also has a dropdown list that allows me to select a product from the product table
I want to be able to create a Add or Edit view that allow me to insert the OrderDate into the OrderTable and also insert the OrderID and selected ProductID into OrderProduct.
What steps do I need to do here.
I have created an OrderController and ticked the "Add Actions" and than added a Create View which looks like this
#model Test.OrderProduct
#{
ViewBag.Title = "Create2";
}
<h2>Create2</h2>
<script src="#Url.Content("~/Scripts/jquery.validate.min.js")" type="text/javascript"></script>
<script src="#Url.Content("~/Scripts/jquery.validate.unobtrusive.min.js")" type="text/javascript"></script>
#using (Html.BeginForm()) {
#Html.ValidationSummary(true)
<fieldset>
<legend>OrderProduct</legend>
<div class="editor-label">
#Html.LabelFor(model => model.OrderID)
</div>
<div class="editor-field">
#Html.EditorFor(model => model.OrderID)
#Html.ValidationMessageFor(model => model.OrderID)
</div>
<div class="editor-label">
#Html.LabelFor(model => model.ProductID)
</div>
<div class="editor-field">
#Html.EditorFor(model => model.ProductID)
#Html.ValidationMessageFor(model => model.ProductID)
</div>
<p>
<input type="submit" value="Create" />
</p>
</fieldset>
}
<div>
#Html.ActionLink("Back to List", "Index")
</div>
This creates the view that contains a textbox for both OrderID and ProductID however no date.
My controller CreatePost hasnt been changed
[HttpPost]
public ActionResult Create(FormCollection collection)
{
try
{
var data = collection;
// TODO: Add insert logic here
// db.Orders.AddObject(collection);
return RedirectToAction("Index");
}
catch
{
return View();
}
}
My questions are,
1.How do I swap out ProductID textbox to be a dropdown which is populated from Product
2.How do I get the data from FormCollection collection? I thought of just a foreach however I dont know how to get the strongly typed name
Any help for a newbie would be very helpful.
Thank you!

First thing's first, don't bind to the Order entity. Never bind to an EF object, always try and use a ViewModel. Makes life simpler for the View, and that is the goal here.
So, have a ViewModel like this:
public class CreateOrderViewModel
{
public int OrderId { get; set; }
public DateTime OrderDate { get; set; }
public int SelectedProductId { get; set; }
public IEnumerable<SelectListItem> Products { get; set; }
}
That's it right now.
Return that to your View in your [HttpGet] controller action:
[HttpGet]
public ActionResult Create()
{
var model = new CreateOrderViewModel
{
Products = db.Products
.ToList() // this will fire a query, basically SELECT * FROM Products
.Select(x => new SelectListItem
{
Text = x.ProductName,
Value = x.ProductId
});
};
return View(model);
}
Then to render out the list of Products: (basic HTML excluded)
#model WebApplication.Models.CreateOrderViewModel
#Html.DropDownListFor(model => model.SelectedProductId, Model.Products)
The only thing i don't know how to do is bind to the DateTime field. I'm guessing you would need an extension method (HTML Helper) which renders out a Date Picker or something. For this View (creating a new order), just default to DateTime.Now.
Now, onto the [HttpPost] controller action:
[HttpPost]
public ActionResult Create(CreateOrderViewModel model)
{
try
{
// TODO: this manual stitching should be replaced with AutoMapper
var newOrder = new Order
{
OrderDate = DateTime.Now,
OrderProduct = new OrderProduct
{
ProductId = SelectedProductId
}
};
db.Orders.AddObject(newOrder);
return RedirectToAction("Index");
}
catch
{
return View();
}
}
Now, i also think your EF model needs work.
To me (in English terms), a Product can have many orders, and an Order can have many Products.
So, it should be a many-to-many. Currently it's a 1-1 with a redundant join table. Did you generate that from a DB? If so, your DB possibly needs work.
You should have a navigational property called Products on the Order entity, which references a collection of Product, made possible by a silent join to the join table in the many-to-many.
This also means you no longer have a DropDownList, but a MultiSelectDropDownList.

Thanks Craig. Your few days (as at time of posting) of MVC have solved my few days of trying to get the selected value back from DropDownListFor.
I had no problem in the Create view in getting the selected value of the DDLF, but the Edit view was a completely different matter - nothing I tried would get the selected value back in the Post. I noticed the selected value was lurking in the AttemptedValue of the ModelState, and so Dr.Google referred me here.
I had this in my view
#Html.DropDownList(model => model.ContentKeyID, Model.ContentKeys, Model.ContentKeyName)
where ContentKeys is a SelectList populated from the DB via a ViewModel, and ContentKeyName is the curently selected name.
The wierd thing is, I have another DDL on the view populated in an identical manner. This one works. Why, I don't know. It is the second DDL on the form, but I can't see that making a difference.
I read somewhere else it might have been that I was using Guids as the Id, but that didn't seem to make a difference - I changed to Int32, but don't think I had to - I think it's enums that disagree with DDLF. Nullables seemd to make no difference either.
Now that I've added the form collection to my Post ActionResult, and get the selected value using
-view
#Html.DropDownList("ContentKey", Model.ContentKeys)
-in controller (Post)
contentKeyId = int.Parse(form.GetValue("ContentKey").AttemptedValue);
all is good, and I can get on with more exciting things. Why is that the simplest things can hold you up for so long?

I have been struggling with this over the last day or so too. I'll share my limited knowledge in the hope that it will help someone else.
Note that I use a singleton with a pre-populated list to keep my example application small (i.e. no EF or DB interaction).
To show the ProductList you will need to have a ViewBag or ViewData item which contains the ProductList.
You can set this up in the Controller with something like
ViewData["ProductList"] = new SelectList(Models.MVCProduct.Instance.ProductList, "Id", "Name", 1);
Then update your View to something like:
<div class="editor-field">#Html.DropDownList("ProductList")</div>
For the Post/Create/Update step you need to look into the FormCollection to get your results. Reading other posts it sounds like there used to be a bug in here, but it's fixed now so ensure you have the latest. For my example I have a DropDownList for Product so I just get the selected Id and then go searching for that Product in my list.
[HttpPost]
public ActionResult Create(FormCollection form )//Models.MVCOrder newOrder)
{
MVC.Models.MVCOrder ord = Models.MVCOrder.Instance.CreateBlankOrder();
//Update order with simple types (e.g. Quantity)
if (TryUpdateModel<MVC.Models.MVCOrder>(ord, form.ToValueProvider()))
{
ord.Product = Models.MVCProduct.Instance.ProductList.Find(p => p.Id == int.Parse(form.GetValue("ProductList").AttemptedValue));
ord.Attribute = Models.MVCAttribute.Instance.AttributeList.Find(a => a.Id == int.Parse(form.GetValue("attributeId").AttemptedValue));
UpdateModel(ord);
return RedirectToAction("Index");
}
else
{
return View(ord);
}
}
I've only been working on MVC3 for the last few days, so any advice on improving the above would be appreciated.