I understand that I can use #Html.HiddenFor(m => m.parameter) and when the form is submitted, that parameter will be passed to the controller. My model has many properties.
Is there a shorter way of passing the entire model at once to the controller or must I do it one by one each time?
The model will be passed to the controller in its entirety, but the values of properties that are not bound by input or hidden fields will be lost.
You have to either bind the properties in the form on the client-side, or re-fetch the entity on the server-side.
You seem to be asking for something like #Html.HiddenFor(m => m.Model), and that is not possible. Sorry
One thing to keep in mind, if you have tons of hidden fields, you may be sending more data to the view than you really need. Consider employing view models
For anyone else who looks at this you can do a #Html.EditorForModel() in a hidden div. You'd also have to use #Html.EditorFor(model => model.ObjectProperty) for each object property of the model.
<div hidden="hidden">
#Html.EditorForModel()
#Html.EditorFor(model => model.ObjectProperty)
#Html.EditorFor(model => model.ListOfObjectsProperty)
</div>
The entire model will be posted if you are using a FORM element. Your elements using the Model obviously need to be inside the form element
You can also POST the form yourself say by using JQuery
See this other stack issue for that : jQuery AJAX submit form
Have a close look at the anwser by "Alfrekjv"
This is already built in. Consider this model:
public class MyModel
{
public string PropertyA { get; set; }
public string parameter { get; set; }
}
and now consider this action:
[HttpPost]
public ActionResult PostSomeData(MyModel model)
{
}
MVC will leverage the FormCollection and fill in the MyModel class where it can. If you don't have the PropertyA in the form then it will be null. But since you have an input for the parameter property it will be filled in.
You can check only the properties you want:
if (this.ModelState.IsValidField("Name"))
{
// .....
}
instead of:
if (this.ModelState.IsValid)
{
// .....
}
#using (Ajax.BeginForm("my_function", "my_controller", new AjaxOptions { InsertionMode = InsertionMode.Replace }, mymodel))
Related
I'm working on an ASP.NET MVC 5 application and the project owner is concerned about "under-posting" issues caused by validating non-nullable types (as mentioned in http://bradwilson.typepad.com/blog/2010/01/input-validation-vs-model-validation-in-aspnet-mvc.html and http://www.asp.net/web-api/overview/formats-and-model-binding/model-validation-in-aspnet-web-api).
I created a test case to replicate this issue in ASP.NET MVC 5 but without luck.
Model:
public class ContactModel
{
[Required]
public Int32 data1 { get; set; }
public Int32 data2 { get; set; }
}
View:
<div class="form-group">
#Html.LabelFor(model => model.data1)
<div>
#Html.EditorFor(model => model.data1)
</div>
</div>
<div>
#Html.LabelFor(model => model.data2)
<div>
#Html.EditorFor(model => model.data2)
</div>
</div>
Controller:
public ActionResult Index(Models.ContactModel contact)
{
if (ModelState.IsValid)
{
Response.Write("modelstate is valid<br>");
return View();
}
else
{
Response.Write("modelstate is invalid<br>");
return View();
}
}
It seems that when data1 and data2 are null in the post, their values in the model (contact) will be 0. However, ModelState.IsValid will also be false (instead of true as shown in the two articles).
What I have:
What the second article showed:
I couldn't find any information regarding changes on how model validation works in ASP.NET MVC, so I'm guessing I did something wrong with my test case. Any thought and suggestion are appreciated.
The reason your ModelState is false is because the post is providing form values from each property in your model. Essentially the Model binding system is checking the validity of both data1 and data2 fields as you have #Html.EditorFor helpers explicitly written for both properties in your view (so no underposting is actually going on).
I did successfully replicate the under-posting concerns from the articles. Simply remove one of the EditorFor helpers in your view, so you're actually underposting. With both helpers present, there's no underposting going on. So the view looks like this now (note I added the validation helper for both properties to get feedback in the view on what's going on):
View:
<div class="form-group">
#Html.LabelFor(model => model.data1)
<div>
#Html.EditorFor(model => model.data1)
#Html.ValidationMessageFor(model => model.data1)
#Html.ValidationMessageFor(model => model.data2)
</div>
</div>
Make sure to leave the #Html.EditorFor helper completely off for the data2 property. Now fill in zero in the form field (you'll only one form field in the view of course now), and post to your action.
ModelState will come back as true in this scenario, even though only one form field is being posted. Not a good result if someone does underpost! So here's the (slightly modified) original model class where underposting issues will occur in the case a form field is left off of your form (note the Required attributes don't make any difference in this situation as both properties are value types):
//You could add the Required attribute or not, doesn't matter at this point.
//The concern here is that the Modelstate will still come back as Valid
//in the case of a form field being left off of your form (or someone underposts).
//So to replicate underposting issues, make sure to comment or delete
//at least one Html.EditorFor helper in the view.
//[Required] Underposting will occur regardless if this is marked required or not,
//so be careful if someone does underpost your form.
public Int32 data1 { get; set; }
//[Required]
public Int32 data2 { get; set; }
Now the solution if you want to solve the underposting issue:
Simply mark both properties as required and make them nullable as mentioned in the articles you provided, like so:
[Required]
public Int32? data1 { get; set; }
[Required]
public Int32? data2 { get; set; }
Now when the view is posted with a missing #Html.EditorFor helper or a missing form field, the ModelState Validation will come back as false, and you're protected from underposting issues.
Am almost embarassed that I can't get this to work. I have a model like this:
public class Test
{
public string Test1 {get; set; }
public string Test2 {get; set; }
}
I have a razor view which correctly displays both Test1 and Test2. Test1 is displayed just like this:
#Html.LabelFor(model => mode.Test1)
#Html.Test1
Test2 is displayed like this:
#Html.LabelFor(model => model.Test2)
#Html.EditorFor(model => model.Test2)
i.e. I just want to display Test1, but want the user to be able to edit Test2.
These are within a form:
#using(Hmtl.BeginForm("Action1", "Controller1", FormMethod.Post)
In Controller1.Action1 it receives the model:
public ActionResult Action1(Test m)
{
}
but in here m.Test1 is null, m.Test2 is correctly populated. m.test1 is correctly displayed in the view.
Am confused.com
Thanks in advance,
Ray
The model binder only sees the form values which are posted from the HTML form, which are only from form elements. This doesn't generate such an element:
#Html.Test1
That may display the value to which the view is bound (does it really? I've never seen it done like that, maybe that should be #Model.Test1?) but there needs to be an HTML form element of some kind to post a value back to the server. (input, select, hidden, etc.)
For fun, take a look at the HTML generated in the browser. They're just standard form elements with values, there's nothing storing the whole model anywhere. The model binder just tries to intelligently re-construct a model based on the name/value pairs sent from the HTML form.
Try adding a hidden field to the form as well:
#Html.LabelFor(model => model.Test1)
#Model.Test1
#Html.HiddenFor(model => model.Test1)
This should create an input type="hidden" in the form with that value, which would be included when posting the values to the controller action.
This very well may end up being a very silly question in a way but basically I have this "form" in a model that gets attached to my View as the form but I haven't been able to actually pass any data do it from the View. It only has two properties: an Id property and a String property. I've been trying to fill the String property with text from a hidden text box on the page with no luck.
Form code:
public class AllocateListForm
{
public int Id { get; set; }
public virtual string HiddenText { get; set; }
}
Relevant View code:
<% using (Html.BeginForm("SaveExit", "User", new { }, FormMethod.Post, new { id = "selectExitPoints" })) { %>
<fieldset>
<input type="hidden" id="HiddenText" />
</fieldset>
<% } %>
There is JQuery behind the scenes that fills HiddenText with text and I can assure you that it is filling. There is also JQuery behind the scenes that performs an Ajax submission and I can promise you that code works as it is used elsewhere in the application without a problem. When I perform the action that submits the form to the server and I go to my controller code that this points to, I have a breakpoint set so I can go into the console and check if the HiddenText field on the form has any data it is null. Can anybody point me in the right direction?
If you assign the input's name to be "HiddenText" the model binder should pick it up. I'm assuming that your controller action accepts an AllocateListForm as a parameter.
<input type="hidden" name="HiddenText" id="HiddenText" />
You can also use Html Helpers like so:
#Html.HiddenFor(model => model.HiddenText, new { id = "HiddenText" })
EDIT: Add an AllocateListForm as a property of your main model and then change the helper to be #Html.HiddenFor(model => model.MyAllocateListForm.HiddenText)
This should do the trick, if you want to do it the Razor-way.
#Html.HiddenFor(model => model.HiddenText);
I don't see this problem too often but I've got a .cshtml that uses a layout. In the layout I've got:
#using (Html.BeginForm(null, null, FormMethod.Post, new { #class = "someCssClass", #id = "UserForm" }))
{
...rest of the code
}
My main .cshtml using this layout has the model defined at the top as we always do:
#model CarViewModel
#{
Layout = "~/Views/Shared/_CarLayout.cshtml";
}
When It gets back to my action method, I get nulls for all values of the model:
public ActionResult Cars(CarViewModel model)
{
carBL.RemoveCars(model.CarIds, model.DealerId);
...
}
Not sure what I need to do here and why this is happening. Usually I just get it back successfully via autobind. It seems to me when the model is used via RAzor in the markup- that gets posted back fine with the returned ViewModel but if I'm not using those fields, it doesn't...so I assume that's how that works and if I don't use them in mark-up I need to send them back as hidden values then to force the persistence since I am not using x fields from the ViewModel (Which would have automatically persisted those fields if I had used them in the form)?
If the values are not bound to a form field, they will come back null.
in the form use the below for things like ID fields.
#Html.HiddenFor(x => x...)
A quick test, to see if the form is being posted correctly would be to modify the signature of your action:
public ActionResult Cars(FormCollection form)
{
...
}
If form is not populated then you have an issue with the form post. As a side, note you could accomplish this when reviewing the post data of the form with a tool like FireBug, Chrome Dev tools or Fiddler if you prefer.
If the form is posting correctly, then I you should check to make sure the name's of the input fields on the form align with the names of the CarViewModel you are expecting.
Not sure if this has been resolved yet, but this is how I do it (partial code):
#model MyProject.ViewModels.MyViewModel
#using (Html.BeginForm())
{
<table>
<tr>
<td>First Name:</td>
<td>#Html.TextBoxFor(x => x.FirstName, new { maxlength = "50" })
#Html.ValidationMessageFor(x => x.FirstName)
</td>
</tr>
</table>
<button id="btnSave" type="submit">Save</button>
<button id="btnCancel" type="button">Cancel</button>
}
Then my action method to handle the HTTP post request:
[HttpPost]
public ActionResult Create(MyViewModel viewModel)
{
// Check for null on viewModel
// Do what needs to be done
}
Doing it this way should not let you loose your values filled in on the form/view.
I have a multi-step file import process. I have a hidden form input in my view that I am trying to populate with the "CurrentStep" from the view model.
<% = Html.HiddenFor(model => model.CurrentStep) %>
CurrentStep is an Enum and I always get the default value rather than the one I provided to the view model. on the other hand this gets me the correct value:
<p><% = Model.CurrentStep %></p>
I realise I could just hand code the hidden input but I want to know: what am I doing wrong? Is there a better way to keep track of the current step between POSTs?
What you are doing wrong is that you are trying to modify the value of a POSTed variable in your controller action. So I suppose you are trying to do this:
[HttpPost]
public ActionResult Foo(SomeModel model)
{
model.CurrentStep = Steps.SomeNewValue;
return View(model);
}
and html helpers such as HiddenFor will always first use the POSTed value and after that the value in the model.
So you have a couple of possibilities:
Remove the value from the modelstate:
[HttpPost]
public ActionResult Foo(SomeModel model)
{
ModelState.Remove("CurrentStep");
model.CurrentStep = Steps.SomeNewValue;
return View(model);
}
Manually generate the hidden field
<input type="hidden" name="NextStep" value="<%= Model.CurrentStep %>" />
Write a custom helper which will use the value of your model and not the one that's being POSTed
My solution was to use Darin's second option, because option 1 (clearing from the model state) means hard coding a string (and the naming convention can be tricky with complex models), and wanted to avoid option 3 because I already have so many custom helpers.
<input type="hidden" name="#Html.NameFor(x => Model.SomeId)" value="#Model.SomeId" />
Just a reminder that you can use Html.NameFor to keep things clean.
Make sure you model property has a "set" operator.
This won't get updated on post-back:
#Html.HiddenFor( m => m.NoSeq)
public Class MyModel
{
int _NoSeq;
public NoSeq
{
get { return _NoSeq };
}
}