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How to: Parameter binding from multiple sources

Currently I'm trying to create a web api based on asp.net core 2.0 and I'd like to create a nested route. In case of a put request it sends a part of the information in the route and another part in the body.
Requirements
The desired url to call would be
https://localhost/api/v1/master/42/details
If we'd like to create a new detail below our master 42 I would expect to send the data of the details in the body while the id of the master comes out of the route.
curl -X POST --header 'Content-Type: application/json' \
--header 'Accept: application/json' \
-d '{ \
"name": "My detail name", \
"description": "Just some kind of information" \
}' 'https://localhost/api/v1/master/42/details'
The outcoming response of the request would be
{
"name": "My detail name",
"description": "Just some kind of information",
"masterId": 42,
"id": 47
}
and a location url within the response header like
{
"location": "https://localhost/api/v1/master/42/details/47
}
Work done so far
To get this to work I created this controller:
[Produces("application/json")]
[Route("api/v1/master/{masterId:int}/details")]
public class MasterController : Controller
{
[HttpPost]
[Produces(typeof(DetailsResponse))]
public async Task<IActionResult> Post([FromBody, FromRoute]DetailCreateRequest request)
{
if(!ModelState.IsValid)
return BadRequest(ModelState);
var response = await Do.Process(request);
return CreatedAtAction(nameof(Get), new { id = response.Id }, response);
}
}
Which uses these classes:
public class DetailCreateRequest
{
public int MasterId { get; set; }
public string Name { get; set; }
public string Description { get; set; }
}
public class DetailResponse
{
public int Id { get; set; }
public int MasterId { get; set; }
public string Name { get; set; }
public string Description { get; set; }
}
The problem
So far most of the stuff works as expected. The only thing that really doesn't work is merging the MasterId from the route into the DetailCreateRequest that comes from the body.
First try: Use two attributes on the parameter
I tried to combine these two things by this action call:
public async Task<IActionResult> Post([FromBody, FromRoute]DetailCreateRequest request)
But the incoming object only had a MasterId of zero. If I change the order of the two attributes, then only the id from the route will be taken and all values within the body are ignored (so seems to be first attribute wins).
Second try: Use two different parameters in action
Another approach that I tried was this action call:
public async Task<IActionResult> Post([FromRoute]int masterId, [FromBody]DetailCreateRequest request)
In the first spot this looks okay, cause now I have both values within the controller action. But my big problem with this approach is the model validation. As you can see in the above code I check ModelState.IsValid which was filled through some checks from FluentValidation, but these checks can't be really done, cause the object wasn't build up correctly due to the missing master id.
(Not-working) Idea: Create own attribute with merge parameters
Tried to implement something like this:
public async Task<IActionResult> Post([FromMultiple(Merge.FromBody, Merge.FromRoute)]DetailCreateRequest request)
If we already would have something like this, that would be great. The order of the arguments within the attribute would give out the order in which the merge (and possible overwrites) would happen.
I already started with implementing this attribute and creating the skeleton for the needed IValueProvider and IValueProviderFactory. But it seems to be a quite lot of work. Especially finding all the nifty details to make this work seamlessly with the whole pipeline of asp.net core and other libraries I'm using (like swagger through swashbuckle).
So my question would be, if there already exists some mechanism within asp.net core to achieve such a merge or if anybody is aware about an already existing solution or about a good example on how to implement such a beast.
Solution so far: Custom ModelBinder
After getting the answer from Merchezatter I look into how to create a custom model binder and came up with this implementation:
public class MergeBodyAndValueProviderBinder : IModelBinder
{
public Task BindModelAsync(ModelBindingContext bindingContext)
{
if (bindingContext == null)
throw new ArgumentNullException(nameof(bindingContext));
var body = bindingContext.HttpContext.Request.Body;
var type = bindingContext.ModelMetadata.ModelType;
var instance = TryCreateInstanceFromBody(body, type, out bool instanceChanged);
var bindingFlags = BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic;
var setters = type.GetProperties(bindingFlags).Where(property => property.CanWrite);
foreach (var setter in setters)
{
var result = bindingContext.ValueProvider.GetValue(setter.Name);
if (result != ValueProviderResult.None)
{
try
{
var value = Convert.ChangeType(result.FirstValue, setter.PropertyType);
setter.SetMethod.Invoke(instance, new[] { value });
instanceChanged = true;
}
catch
{ }
}
}
if (instanceChanged)
bindingContext.Result = ModelBindingResult.Success(instance);
return Task.CompletedTask;
}
private static object TryCreateInstanceFromBody(Stream body, Type type, out bool instanceChanged)
{
try
{
using (var reader = new StreamReader(body, Encoding.UTF8, false, 1024, true))
{
var data = reader.ReadToEnd();
var instance = JsonConvert.DeserializeObject(data, type);
instanceChanged = true;
return instance;
}
}
catch
{
instanceChanged = false;
return Activator.CreateInstance(type);
}
}
}
It tries to deserialize the body into the desired object type and afterwards tries to apply further values from the available value providers. To get this model binder to work I had to decorate the destination class with the ModelBinderAttribute and made the MasterId internal, so that swagger doesn't announce it and JsonConvert doesn't deserialize it:
[ModelBinder(BinderType = typeof(MergeBodyAndValueProviderBinder))]
public class DetailCreateRequest
{
internal int MasterId { get; set; }
public string Name { get; set; }
public string Description { get; set; }
}
Within my controller the action method parameters are still containing the [FromBody] flag, cause it is used by swagger to announce on how the method can be called, but it never will be called, cause my model binder has a higher priority.
public async Task<IActionResult> Post([FromBody]DetailCreateRequest request)
So it is not perfect, but works good so far.

That is looks like a right choice:
[HttpPost]
[Produces(typeof(DetailsResponse))]
public async Task<IActionResult> Post([FromRoute]int masterId, [FromBody]DetailCreateRequest request) {
//...
}
But if you have some problems with domain model validation, create custom Dto object without master Id.
Otherwise you can use custom model binder, and then work with arguments from action and binding contexts.

I'm not sure if this works in Asp.Net-Core 2.0, but we use the following in 3.1 to have a single request object which gets its properties from multiple locations:
// Annotate the action parameter with all relevant attributes
public async Task<IActionResult> Post([FromBody][FromRoute][FromQuery]DetailCreateRequest request) { ... }
// Annotate each property separately, so the binder(s) don't overwrite
public class DetailCreateRequest
{
[FromRoute]
public int MasterId { get; set; }
[FromBody]
public string Name { get; set; }
[FromQuery]
public string Description { get; set; }
}

It works with .Net 6:
[HttpPost]
[Route("{id}")]
public async Task<ActionResult<CustomerResponse>> Post([FromRoute, FromBody] CustomerPostRequest request)
{
return Ok();
}
public class CustomerPostRequest
{
[FromRoute(Name = "id")]
public int Id { get; set; }
[FromBody]
public string Name { get; set; }
}
Set the your required "source" attributes on the single request object parameter, and inside this object add each property the relevant "source" attribute.
Make sure the FromBody is the last one (it didn't work when I switched them).

MVC - how to send to the partial view ViewModel containing a list

I am the beginner in MVC and I have a web application, where in my controller I declare a list of objects (feedback from visitors) and then send it to the view, which displays it. It looks like this. Declaration:
public class TrekFeedbackItem
{
public string trekid { get; set; }
public string comment { get; set; }
public string author { get; set; }
public TrekFeedbackItem(string trekid, string comment, string author)
{ this.trekid = trekid;
this.comment = comment;
this.author = author;
}
}
And usage:
List<TrekFeedbackItem> feedbackList = new List<TrekFeedbackItem>
{
//constructor called, data entered into the list
}
return View(trekname, feedbackList);
However, now I need to pass also another list, lets call it relatedblogsList. As a first step, I decided to encapsulate my feedbackList into the ViewModel (and once it works, add another list of different objects.)
public class TrekViewModel
{
public List<TrekFeedbackItem> feedback { get; set; }
}
and fill the data like this:
TrekViewModel trek = new TrekViewModel();
trek.feedback = new List<TrekFeedbackItem>
{
//insert data here
};
return View(view, trek);
The problem is - how to send this model to the partial view and how to access it?
Thank a lot

You can pass data into the partial view like below
from the controller return this view:
return PartialView("_partial_viewname", trek);
then in the beginning of the partial view:
#model Models.TrekViewModel
after that you can use Model.feedback inside the partial view.

Set return type of your action controller to "PartialView" rather than "View".
return PartialView("_yourPartialViewName", yourObject);
In case, if application does not work as expected, build it and re-run it.

View expecting IEnumerable

Well im kinda new in Asp.net Mvc and im learning alone from scratch, i have a aplicattion that controls expends and earnings and what i am trying to do now is, basing on a list of earnings and expends give me the balance from a user, im having a lot of problems trying to control this and i dont know if i am doing it the right way
Here is my model:
public class Balance
{
public int BalanceId { get; set; }
public List<Expense> Despesas { get; set; }
public List<Earning> Rendimentos { get; set; }
public string ApplicationUserId { get; set; }
}
Soo what i did was, first trying to control when the user inserts a Earning or a row like, verifying if the User already exists on the database in the control method Create on the expenses and in the earning, if it doesnt exist he add the aplicationUserId and the expensive or the earning.
I want that the balance appears in every page, soo i added this to my Layout.cshtml
<li>#Html.Action("GetBalance", "Home")</li>
it calls the controller GetBalance:
public PartialViewResult GetBalance()
{
var userId = User.Identity.GetUserId();
var balance = db.Balance.Where(d => d.ApplicationUserId == userId);
return PartialView("_GetBalance",balance);
}
Send to the view _GetBalance the balance model:
#model <MSDiary.Models.Balance>
<p>Saldo: #GetBalance()</p>
#functions
{
HtmlString GetBalance()
{
decimal saldo = 0;
if (Model.Expense.Count != 0 || Model.Earning.Count != 0)
{
foreach (var item in Model.Despesas)
{
balance += item.EarningValue;
}
foreach (var item in Model.Rendimentos)
{
balance -= item.ExpenseValor;
}
}
return new HtmlString(balance.ToString());
}
}
What i want to know is, if there is a easyer way to do this, or what i can do to do what i want, i cant get it why my view expects something different can someone explain me what i am doing wrong?
Ps: Sorry for the long post and English, but i want to learn more :)

Firstly, the model #model <MSDiary.Models.Balance> needs to be changed to:
#model IEnumerable<MSDiary.Models.Balance>
Also, the method GetBalance should ideally be placed in a class not in GetBalance partial view. You could achieve this two ways, either through extension methods or have a Balance View Model that has the calculated balance as a property which is then passed down to your view.
As an example via an extension method:
public static class BalanceExtensions
{
public static string GetBalance(this Balance balance)
{
string displayBalance = "0:00";
// Your logic here
return displayBalance;
}
}
And then in your Partial View you can use the new HTML Helper:
#Html.GetBalance();
As an additional note I would change List to IEnumerable for expenses and earnings as it appears you are only exposing the data and not manipulating the data.
Your model would then look like:
public class Balance
{
public int BalanceId { get; set; }
public IEnumerable<Expense> Despesas { get; set; }
public IEnumerable<Earning> Rendimentos { get; set; }
public string ApplicationUserId { get; set; }
}

#Filipe Costa A few things here.
You should probably name your view the same thing as your method. The underscore preceding the name is fairly standard so I would suggest using that same name for the method. If the name of the method and view are the same you can simply pass in the model and not have to do the name + model signature of PartialView method. It's simpler.
Aside from that your code is fine but your .cshtml partial view should have this for the first line. That will accept the list you're passing.
#model IEnumerable<MSDiary.Models.Balance>
<h1>#Model.BalanceId</h1>
#*Do other stuff!*#

Retrieving records from another SQL Server database - Umbraco

I'm working on a website, where I need to retrieve pricelists, from another database on the same SQL Server as my Umbraco database.
It's a requirement that it has to be in a separate database.
I have made a new connection string Pricelist and used EF database-first.
PriceList repository:
namespace UmbracoCMS.Repository{
using System;
using System.Collections.Generic;
public partial class Prisliste
{
public string Kode { get; set; }
public string Speciale { get; set; }
public string Ydelsesgruppe { get; set; }
public string Gruppe { get; set; }
public string Ydelse { get; set; }
public string Ydelsestekst { get; set; }
public string Anaestesi { get; set; }
public string Indlæggelse { get; set; }
public Nullable<double> Listepris { get; set; }
public Nullable<int> WebSort { get; set; }
public string YdelsesTekstDK { get; set; }
public string Frapris { get; set; }
public Nullable<int> Sortering { get; set; }
}
}
PriceListController class:
using System;
using System.Linq;
using System.Web.Mvc;
using UmbracoCMS.Repository;
namespace UmbracoCMS.Controllers{
public class PriceListController : Umbraco.Web.Mvc.SurfaceController {
[HttpGet]
public PartialViewResult GetPriceList(string contentTitle){
var db = new PricelistContext();
var query = from b in db.Prislistes orderby b.Speciale select b;
Console.WriteLine("records in the database:");
foreach (var item in query)
{
Console.WriteLine(item.Speciale);
}
return PartialView("~/views/partials/PriceList.cshtml");
}
}
}
What I want is to load the prices for a treatment, based on a property on the document type. I'm just not sure how do this in umbraco since I'm fairly new a umbraco.
So when a treatment page is requested, I need to take the property ContentTitle value. Use it to retrieve all records with the same Speciale and display them in a list/table.
With a query
.where(b.Speciale = contentTitle)
It would be great if someone could help a little, or lead me in the right direction.
Also is it possible to do it in the same http request? Or should I use partial view or macros to both get the properties of the document type, from the umbraco database, and the records from the pricelist database at the same time when a user go to the treatment page?
Or is there a better way to do this?
Update:
Thanks a lot, for the great answer Ryios.
I got a question more.
using System;
using System.Linq;
using System.Web.Mvc;
namespace UmbracoCMS.Controllers
{
public class PriceListSurfaceController : Umbraco.Web.Mvc.SurfaceController
{
public ActionResult GetPriceList(string contentTitle)
{
PricelistContext.RunInContext(db =>
{
var result = db.Prislistes.OrderBy(p => p.Speciale);
});
return View(result);
}
}
}
I got it working, so it call the method and the data from the Pricelist Database is shown in:
var result = db.Prislistes.OrderBy(p => p.Speciale);
Now I just need to get the list of prices out to the view again, so I can show a list or table of the prices.
Do you have a suggestion on how I can this in Umbraco. Normally I would return a ViewModel in MVC like:
return View(new ListViewModel(result));
and use it in the view like:
#model Project.ViewModels.ListViewModel
So I can loop through it.
But I want to still have the properties from the the "Home"/"TreatmentPage" Document type.
Should I do it with a partialView or is there a better way?
Solved
I thought I wanted to share it, if anyone else is in a similar situaction.
Controller:
namespace UmbracoCMS.Controllers
{
public class PriceListSurfaceController : Umbraco.Web.Mvc.SurfaceController
{
public PartialViewResult PriceList(string contentTitle)
{
List<Prisliste> result = null;
PricelistContext.RunInContext(db =>
{
result = db.Prislistes.Where(p => p.Speciale == contentTitle)
.OrderBy(p => p.Speciale).ToList();
});
var model = result.Select( pl => new PrislistVm()
{
Speciale = pl.Speciale,
Listepris= pl.Listepris
});
return PartialView(model);
}
}
}
ViewModel:
namespace UmbracoCMS.ViewModels
{
public class PrislistVm
{
public PrislistVm()
{
Results = new List<Prisliste>();
}
public List<Prisliste> Results { get; set; }
public string Speciale { get; set; }
public double listepris { get; set; }
}
}
View/PriceListSurface:
#model IEnumerable<UmbracoCMS.ViewModels.PrislistVm>
#{
ViewBag.Title = "PriceList";
}
<h2>PriceList</h2>
#foreach (var item in Model)
{
#item.Speciale
#item.Listepris
}

Your going to have a memory leak if you load your EF context like that. I recommend creating a method to wrap it for you with a llambda callback. Put it in your context class.
public static void RunInContext(Action<PricelistContext> contextCallBack)
{
PricelistContext dbContext = null;
try
{
dbContext = new PricelistContext();
contextCallBack(dbContext);
}
finally
{
dbContext.Dispose();
dbContext = null;
}
}
//Example Call
PricelistContext.RunInContext(db => {
var result = db.PrisListes.OrderBy(p => p.Speciale);
//loop through your items
});
To get the Value of the DocumentType, it depends on the calling context. Assuming you are using a Razor Template that is attached to the document type, that is associated with a Content Page.
#inherits Umbraco.Web.Mvc.UmbracoTemplatePage
#{
Layout = "ContentPageLayout.cshtml";
}
#* Call GetPriceList on PriceListController with Parameter contentTitle *#
#Html.Action("GetPriceList", "PriceListSurface", new { contentTitle = Model.Content.GetPropertyValue<string>("ContentTitle") });
In the above example, I have created a document type with a property called ContentTitle that is associated with a view called ContentPage. Then I created content in the backoffice Content section called "Home" that uses the document type. Giving me a url like
http://localhost/home
Also, your SurfaceController will not work. Umbraco's logic for mapping the routes for surface controllers has some requirements for your surface controller's naming conventions. You have to end the name of the class with "SurfaceController" and then it get's called PriceListSurfaceController, then it maps the controller with a name of "PriceListSurface".
Here's the documentation for the SurfaceController features.
http://our.umbraco.org/documentation/Reference/Mvc/surface-controllers
Using a surface controller is the right logic. It's not good practice to have your Data Layer code calls in the UmbracoTemplatePage. 1, because RazorTemplates are interpreted/compiled and SurfaceController's are JIT compiled int the dll, so SurfaceController code is WAY faster. 2 Because you can make asynchronous Controller calls in MVC Razor. If it was all in the view it would make it really difficult to convert everything to be asynchronous. It's best to keep server side logic in a controller.
Optionally, you can Hijack an Umbraco route and replace it with a custom controller that doesn't have to inherit from SurfaceController, which makes it possibly to surface content to the browser that is or isn't part of umbraco.
http://our.umbraco.org/documentation/Reference/Mvc/custom-controllers
You can also create a new section in the backoffice to manage your Price List "the ui framework for building one is written against AngularJS"
http://www.enkelmedia.se/blogg/2013/11/22/creating-custom-sections-in-umbraco-7-part-1.aspx

Disable Required validation attribute under certain circumstances

I was wondering if it is possible to disable the Required validation attribute in certain controller actions. I am wondering this because on one of my edit forms I do not require the user to enter values for fields that they have already specified previously. However I then implement logic that when they enter a value it uses some special logic to update the model, such as hashing a value etc.
Any sugestions on how to get around this problem?
EDIT:
And yes client validation is a problem here to, as it will not allow them to submit the form without entering a value.

This problem can be easily solved by using view models. View models are classes that are specifically tailored to the needs of a given view. So for example in your case you could have the following view models:
public UpdateViewView
{
[Required]
public string Id { get; set; }
... some other properties
}
public class InsertViewModel
{
public string Id { get; set; }
... some other properties
}
which will be used in their corresponding controller actions:
[HttpPost]
public ActionResult Update(UpdateViewView model)
{
...
}
[HttpPost]
public ActionResult Insert(InsertViewModel model)
{
...
}

If you just want to disable validation for a single field in client side then you can override the validation attributes as follows:
#Html.TextBoxFor(model => model.SomeValue,
new Dictionary<string, object> { { "data-val", false }})

I know this question has been answered a long time ago and the accepted answer will actually do the work. But there's one thing that bothers me: having to copy 2 models only to disable a validation.
Here's my suggestion:
public class InsertModel
{
[Display(...)]
public virtual string ID { get; set; }
...Other properties
}
public class UpdateModel : InsertModel
{
[Required]
public override string ID
{
get { return base.ID; }
set { base.ID = value; }
}
}
This way, you don't have to bother with client/server side validations, the framework will behave the way it's supposed to. Also, if you define a [Display] attribute on the base class, you don't have to redefine it in your UpdateModel.
And you can still use these classes the same way:
[HttpPost]
public ActionResult Update(UpdateModel model)
{
...
}
[HttpPost]
public ActionResult Insert(InsertModel model)
{
...
}

You can remove all validation off a property with the following in your controller action.
ModelState.Remove<ViewModel>(x => x.SomeProperty);
#Ian's comment regarding MVC5
The following is still possible
ModelState.Remove("PropertyNameInModel");
Bit annoying that you lose the static typing with the updated API. You could achieve something similar to the old way by creating an instance of HTML helper and using NameExtensions Methods.

Client side
For disabling validation for a form, multiple options based on my research is given below. One of them would would hopefully work for you.
Option 1
I prefer this, and this works perfectly for me.
(function ($) {
$.fn.turnOffValidation = function (form) {
var settings = form.validate().settings;
for (var ruleIndex in settings.rules) {
delete settings.rules[ruleIndex];
}
};
})(jQuery);
and invoking it like
$('#btn').click(function () {
$(this).turnOffValidation(jQuery('#myForm'));
});
Option 2
$('your selector here').data('val', false);
$("form").removeData("validator");
$("form").removeData("unobtrusiveValidation");
$.validator.unobtrusive.parse("form");
Option 3
var settings = $.data($('#myForm').get(0), 'validator').settings;
settings.ignore = ".input";
Option 4
$("form").get(0).submit();
jQuery('#createForm').unbind('submit').submit();
Option 5
$('input selector').each(function () {
$(this).rules('remove');
});
Server Side
Create an attribute and mark your action method with that attribute. Customize this to adapt to your specific needs.
[AttributeUsage(AttributeTargets.All)]
public class IgnoreValidationAttribute : ActionFilterAttribute
{
public override void OnActionExecuting(ActionExecutingContext filterContext)
{
var modelState = filterContext.Controller.ViewData.ModelState;
foreach (var modelValue in modelState.Values)
{
modelValue.Errors.Clear();
}
}
}
A better approach has been described here Enable/Disable mvc server side validation dynamically

Personally I would tend to use the approach Darin Dimitrov showed in his solution.
This frees you up to be able to use the data annotation approach with validation AND have separate data attributes on each ViewModel corresponding to the task at hand.
To minimize the amount of work for copying between model and viewmodel you should look at AutoMapper or ValueInjecter. Both have their individual strong points, so check them both.
Another possible approach for you would be to derive your viewmodel or model from IValidatableObject. This gives you the option to implement a function Validate.
In validate you can return either a List of ValidationResult elements or issue a yield return for each problem you detect in validation.
The ValidationResult consists of an error message and a list of strings with the fieldnames. The error messages will be shown at a location near the input field(s).
public IEnumerable<ValidationResult> Validate(ValidationContext validationContext)
{
if( NumberField < 0 )
{
yield return new ValidationResult(
"Don't input a negative number",
new[] { "NumberField" } );
}
if( NumberField > 100 )
{
yield return new ValidationResult(
"Don't input a number > 100",
new[] { "NumberField" } );
}
yield break;
}

The cleanest way here I believe is going to disable your client side validation and on the server side you will need to:
ModelState["SomeField"].Errors.Clear (in your controller or create an action filter to remove errors before the controller code is executed)
Add ModelState.AddModelError from your controller code when you detect a violation of your detected issues.
Seems even a custom view model here wont solve the problem because the number of those 'pre answered' fields could vary. If they dont then a custom view model may indeed be the easiest way, but using the above technique you can get around your validations issues.

this was someone else's answer in the comments...but it should be a real answer:
$("#SomeValue").removeAttr("data-val-required")
tested on MVC 6 with a field having the [Required] attribute
answer stolen from https://stackoverflow.com/users/73382/rob above

I was having this problem when I creating a Edit View for my Model and I want to update just one field.
My solution for a simplest way is put the two field using :
<%: Html.HiddenFor(model => model.ID) %>
<%: Html.HiddenFor(model => model.Name)%>
<%: Html.HiddenFor(model => model.Content)%>
<%: Html.TextAreaFor(model => model.Comments)%>
Comments is the field that I only update in Edit View, that not have Required Attribute.
ASP.NET MVC 3 Entity

AFAIK you can not remove attribute at runtime, but only change their values (ie: readonly true/false) look here for something similar .
As another way of doing what you want without messing with attributes I will go with a ViewModel for your specific action so you can insert all the logic without breaking the logic needed by other controllers.
If you try to obtain some sort of wizard (a multi steps form) you can instead serialize the already compiled fields and with TempData bring them along your steps. (for help in serialize deserialize you can use MVC futures)

What #Darin said is what I would recommend as well. However I would add to it (and in response to one of the comments) that you can in fact also use this method for primitive types like bit, bool, even structures like Guid by simply making them nullable. Once you do this, the Required attribute functions as expected.
public UpdateViewView
{
[Required]
public Guid? Id { get; set; }
[Required]
public string Name { get; set; }
[Required]
public int? Age { get; set; }
[Required]
public bool? IsApproved { get; set; }
//... some other properties
}

As of MVC 5 this can be easily achieved by adding this in your global.asax.
DataAnnotationsModelValidatorProvider.AddImplicitRequiredAttributeForValueTypes = false;

I was looking for a solution where I can use the same model for an insert and update in web api. In my situation is this always a body content. The [Requiered] attributes must be skipped if it is an update method.
In my solution, you place an attribute [IgnoreRequiredValidations] above the method. This is as follows:
public class WebServiceController : ApiController
{
[HttpPost]
public IHttpActionResult Insert(SameModel model)
{
...
}
[HttpPut]
[IgnoreRequiredValidations]
public IHttpActionResult Update(SameModel model)
{
...
}
...
What else needs to be done?
An own BodyModelValidator must becreated and added at the startup.
This is in the HttpConfiguration and looks like this: config.Services.Replace(typeof(IBodyModelValidator), new IgnoreRequiredOrDefaultBodyModelValidator());
using Owin;
using your_namespace.Web.Http.Validation;
[assembly: OwinStartup(typeof(your_namespace.Startup))]
namespace your_namespace
{
public class Startup
{
public void Configuration(IAppBuilder app)
{
Configuration(app, new HttpConfiguration());
}
public void Configuration(IAppBuilder app, HttpConfiguration config)
{
config.Services.Replace(typeof(IBodyModelValidator), new IgnoreRequiredOrDefaultBodyModelValidator());
}
...
My own BodyModelValidator is derived from the DefaultBodyModelValidator. And i figure out that i had to override the 'ShallowValidate' methode. In this override i filter the requierd model validators.
And now the IgnoreRequiredOrDefaultBodyModelValidator class and the IgnoreRequiredValidations attributte class:
using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using System.Web.Http.Controllers;
using System.Web.Http.Metadata;
using System.Web.Http.Validation;
namespace your_namespace.Web.Http.Validation
{
public class IgnoreRequiredOrDefaultBodyModelValidator : DefaultBodyModelValidator
{
private static ConcurrentDictionary<HttpActionBinding, bool> _ignoreRequiredValidationByActionBindingCache;
static IgnoreRequiredOrDefaultBodyModelValidator()
{
_ignoreRequiredValidationByActionBindingCache = new ConcurrentDictionary<HttpActionBinding, bool>();
}
protected override bool ShallowValidate(ModelMetadata metadata, BodyModelValidatorContext validationContext, object container, IEnumerable<ModelValidator> validators)
{
var actionContext = validationContext.ActionContext;
if (RequiredValidationsIsIgnored(actionContext.ActionDescriptor.ActionBinding))
validators = validators.Where(v => !v.IsRequired);
return base.ShallowValidate(metadata, validationContext, container, validators);
}
#region RequiredValidationsIsIgnored
private bool RequiredValidationsIsIgnored(HttpActionBinding actionBinding)
{
bool ignore;
if (!_ignoreRequiredValidationByActionBindingCache.TryGetValue(actionBinding, out ignore))
_ignoreRequiredValidationByActionBindingCache.TryAdd(actionBinding, ignore = RequiredValidationsIsIgnored(actionBinding.ActionDescriptor as ReflectedHttpActionDescriptor));
return ignore;
}
private bool RequiredValidationsIsIgnored(ReflectedHttpActionDescriptor actionDescriptor)
{
if (actionDescriptor == null)
return false;
return actionDescriptor.MethodInfo.GetCustomAttribute<IgnoreRequiredValidationsAttribute>(false) != null;
}
#endregion
}
[AttributeUsage(AttributeTargets.Method, Inherited = true)]
public class IgnoreRequiredValidationsAttribute : Attribute
{
}
}
Sources:
Using string debug = new StackTrace().ToString() to find out who is
handeling the model validation.
https://learn.microsoft.com/en-us/aspnet/web-api/overview/advanced/configuring-aspnet-web-api to know how set my own validator.
https://github.com/ASP-NET-MVC/aspnetwebstack/blob/master/src/System.Web.Http/Validation/DefaultBodyModelValidator.cs to figure out what this validator is doing.
https://github.com/Microsoft/referencesource/blob/master/System.Web/ModelBinding/DataAnnotationsModelValidator.cs to figure out why the IsRequired property is set on true. Here you can also find the original Attribute as a property.

If you don't want to use another ViewModel you can disable client validations on the view and also remove the validations on the server for those properties you want to ignore. Please check this answer for a deeper explanation https://stackoverflow.com/a/15248790/1128216

In my case the same Model was used in many pages for re-usability purposes. So what i did was i have created a custom attribute which checks for exclusions
public class ValidateAttribute : ActionFilterAttribute
{
public string Exclude { get; set; }
public string Base { get; set; }
public override void OnActionExecuting(HttpActionContext actionContext)
{
if (!string.IsNullOrWhiteSpace(this.Exclude))
{
string[] excludes = this.Exclude.Split(',');
foreach (var exclude in excludes)
{
actionContext.ModelState.Remove(Base + "." + exclude);
}
}
if (actionContext.ModelState.IsValid == false)
{
var mediaType = new MediaTypeHeaderValue("application/json");
var error = actionContext.ModelState;
actionContext.Response = actionContext.Request.CreateResponse(HttpStatusCode.OK, error.Keys, mediaType);
}
}
}
and in your controller
[Validate(Base= "person",Exclude ="Age,Name")]
public async Task<IHttpActionResult> Save(User person)
{
//do something
}
Say the Model is
public class User
{
public int Id { get; set; }
[Required]
public string Name { get; set; }
[Range(18,99)]
public string Age { get; set; }
[MaxLength(250)]
public string Address { get; set; }
}

This one worked for me:
$('#fieldId').rules('remove', 'required');

Yes it is possible to disable Required Attribute. Create your own custom class attribute (sample code called ChangeableRequired) to extent from RequiredAtribute and add a Disabled Property and override the IsValid method to check if it is disbaled. Use reflection to set the disabled poperty, like so:
Custom Attribute:
namespace System.ComponentModel.DataAnnotations
{
public class ChangeableRequired : RequiredAttribute
{
public bool Disabled { get; set; }
public override bool IsValid(object value)
{
if (Disabled)
{
return true;
}
return base.IsValid(value);
}
}
}
Update you property to use your new custom Attribute:
class Forex
{
....
[ChangeableRequired]
public decimal? ExchangeRate {get;set;}
....
}
where you need to disable the property use reflection to set it:
Forex forex = new Forex();
// Get Property Descriptor from instance with the Property name
PropertyDescriptor descriptor = TypeDescriptor.GetProperties(forex.GetType())["ExchangeRate"];
//Search for Attribute
ChangeableRequired attrib = (ChangeableRequired)descriptor.Attributes[typeof(ChangeableRequired)];
// Set Attribute to true to Disable
attrib.Disabled = true;
This feels nice and clean?
NB: The validation above will be disabled while your object instance is alive\active...