How to do server-side validation using DataAnnotations - asp.net-mvc

I am using ASP.NET MVC 5 and trying to do custom validation using data annotations of a view model object that is instantiated within the controller post method and reloaded from EF. Only a few of the model properties are populated when posting from the client and the rest are reloaded using EF. The model is complex and all parts of it implement IValidatableObject. The code within the Validate method fires for the new view model after everything is loaded correctly, but it does not do anything with the data annotations applied to the model.
So for instance, if my model has the EmailAddress attribute applied to a field, it works great on the client side, but it is ignored on the server side when validating against the new view model. How do I get my Validate method to take the data annotations into account?
Here's the code for the controller action...
[HttpPost]
[ValidateAntiForgeryToken]
public virtual ActionResult SignUp(SignUpEM em) {
if (em == null) {
return RedirectToAction(MVC.Sheet.Index());
}
SignUpSheet signUpSheet = db.GetSignUpSheet(em.SheetId);
SignUpEM newEM = Map.ToSignUpEM(signUpSheet);
foreach (var sourceField in em.Fields) {
FieldEM targetField = newEM.Fields.FirstOrDefault(f => f.FieldDefId == sourceField.FieldDefId && f.Id == sourceField.Id);
if (targetField.FieldType.IsEditable()) {
if (targetField.FieldType.IsBoolean()) {
((BooleanFieldEM)targetField).BooleanValue = ((BooleanFieldEM)sourceField).BooleanValue;
}
else {
targetField.Value = sourceField.Value;
}
targetField.SetFullyLoaded();
}
}
// This line is here to simulate an invalid value passed into an email field.
newEM.Fields[0].Value = "invalid";
newEM.SetFullyLoaded();
ModelState.Clear();
var validationResults = new List<ValidationResult>();
Validator.TryValidateObject(newEM, new ValidationContext(newEM, null, null), validationResults, true);
foreach (var result in validationResults) {
if (result == null) { continue; } // otherwise we need to avoid duplicates.
if (result.MemberNames.Count() == 0)
ModelState.AddModelError(String.Empty, result.ErrorMessage);
else
foreach (var name in result.MemberNames)
ModelState.AddModelError(name, result.ErrorMessage);
}
if (!ModelState.IsValid) {
return View(newEM);
}
SignUp su = Map.ToSignUp(em);
db.AddSignUp(su);
return RedirectToAction(MVC.SignUp.SignUp(em.SheetId));
}
Here's the validation code for SignUpEM...
private bool fullyLoaded;
internal void SetFullyLoaded() {
fullyLoaded = true;
}
public IEnumerable<ValidationResult> Validate(ValidationContext validationContext) {
if (fullyLoaded) {
foreach (var f in Fields)
foreach (var vr in f.Validate(validationContext))
yield return vr;
if (ListIntro == null)
yield return new ValidationResult("ListIntro is required for now.");
}
}
And the validation code for FieldEM...
private bool fullyLoaded;
internal void SetFullyLoaded() {
fullyLoaded = true;
}
public IEnumerable<ValidationResult> Validate(ValidationContext validationContext) {
if (fullyLoaded) {
if (Optional == false && String.IsNullOrEmpty(Value)) {
string message = string.Format("{0} is required.", DisplayName);
yield return new ValidationResult(message);
}
}
}

Related

ASP.NET Core [FromBody] vs MVC 5 binding

I got an MVC 5 application that i'm porting to asp.net Core.
In the MVC application call to controller we're made using AngularJS $resource (sending JSON) and we we're POSTing data doing :
ressource.save({ entries: vm.entries, projectId: vm.project.id }).$promise...
that will send a JSON body like:
{
entries:
[
{
// lots of fields
}
],
projectId:12
}
the MVC controller looked like this :
[HttpPost]
public JsonResult Save(List<EntryViewModel> entries, int projectId) {
// code here
}
How can I replicate the same behaviour with .NET Core since we can't have multiple [FromBody]
you cannot have multiple parameter with the FromBody attibute in an action method. If that is need, use a complex type such as a class with properties equivalent to the parameter or dynamic type like that
[HttpPost("save/{projectId}")]
public JsonResult Save(int projectId, [FromBody] dynamic entries) {
// code here
}
As pointed out in the comment, one possible solution is to unify the properties you're posting onto a single model class.
Something like the following should do the trick:
public class SaveModel
{
public List<EntryViewModel> Entries{get;set;}
public int ProjectId {get;set;}
}
Don't forget to decorate the model with the [FromBody] attribute:
[HttpPost]
public JsonResult Save([FromBody]SaveViewModel model)
{
// code here
}
Hope this helps!
It's still rough but I made a Filter to mimic the feature.
public class OldMVCFilter : IActionFilter
{
public void OnActionExecuted(ActionExecutedContext context)
{
}
public void OnActionExecuting(ActionExecutingContext context)
{
if (context.HttpContext.Request.Method != "GET")
{
var body = context.HttpContext.Request.Body;
JToken token = null;
var param = context.ActionDescriptor.Parameters;
using (var reader = new StreamReader(body))
using (var jsonReader = new JsonTextReader(reader))
{
jsonReader.CloseInput = false;
token = JToken.Load(jsonReader);
}
if (token != null)
{
var serializer = new JsonSerializer();
serializer.DefaultValueHandling = DefaultValueHandling.Populate;
serializer.FloatFormatHandling = FloatFormatHandling.DefaultValue;
foreach (var item in param)
{
JToken model = token[item.Name];
if (model == null)
{
// try to cast the full body as the current object
model = token.Root;
}
if (model != null)
{
model = this.RemoveEmptyChildren(model, item.ParameterType);
var res = model.ToObject(item.ParameterType, serializer);
context.ActionArguments[item.Name] = res;
}
}
}
}
}
private JToken RemoveEmptyChildren(JToken token, Type type)
{
var HasBaseType = type.GenericTypeArguments.Count() > 0;
List<PropertyInfo> PIList = new List<PropertyInfo>();
if (HasBaseType)
{
PIList.AddRange(type.GenericTypeArguments.FirstOrDefault().GetProperties().ToList());
}
else
{
PIList.AddRange(type.GetTypeInfo().GetProperties().ToList());
}
if (token != null)
{
if (token.Type == JTokenType.Object)
{
JObject copy = new JObject();
foreach (JProperty jProp in token.Children<JProperty>())
{
var pi = PIList.FirstOrDefault(p => p.Name == jProp.Name);
if (pi != null) // If destination type dont have this property we ignore it
{
JToken child = jProp.Value;
if (child.HasValues)
{
child = RemoveEmptyChildren(child, pi.PropertyType);
}
if (!IsEmpty(child))
{
if (child.Type == JTokenType.Object || child.Type == JTokenType.Array)
{
// nested value has been checked, we add the object
copy.Add(jProp.Name, child);
}
else
{
if (!pi.Name.ToLowerInvariant().Contains("string"))
{
// ignore empty value when type is not string
var Val = (string)child;
if (!string.IsNullOrWhiteSpace(Val))
{
// we add the property only if it contain meningfull data
copy.Add(jProp.Name, child);
}
}
}
}
}
}
return copy;
}
else if (token.Type == JTokenType.Array)
{
JArray copy = new JArray();
foreach (JToken item in token.Children())
{
JToken child = item;
if (child.HasValues)
{
child = RemoveEmptyChildren(child, type);
}
if (!IsEmpty(child))
{
copy.Add(child);
}
}
return copy;
}
return token;
}
return null;
}
private bool IsEmpty(JToken token)
{
return (token.Type == JTokenType.Null || token.Type == JTokenType.Undefined);
}
}

ASP.NET MVC 5 how to delete a user and its related data in Identity 2.0

I'm following this article to delete a user in Identity 2.0
http://www.asp.net/mvc/tutorials/mvc-5/introduction/examining-the-details-and-delete-methods
However, I need to delete all related records in AspNetUserRoles first and then delete the user.
I found an example which is written in Identity 1.0 and some of methods used inside this example don't exist.
// POST: /Users/Delete/5
[HttpPost, ActionName("Delete")]
[ValidateAntiForgeryToken]
public async Task<ActionResult> DeleteConfirmed(string id)
{
if (ModelState.IsValid)
{
if (id == null)
{
return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
}
var user = await context.Users.FindAsync(id);
var logins = user.Logins;
foreach (var login in logins)
{
context.UserLogins.Remove(login);
}
var rolesForUser = await IdentityManager.Roles.GetRolesForUserAsync(id, CancellationToken.None);
if (rolesForUser.Count() > 0)
{
foreach (var item in rolesForUser)
{
var result = await IdentityManager.Roles.RemoveUserFromRoleAsync(user.Id, item.Id, CancellationToken.None);
}
}
context.Users.Remove(user);
await context.SaveChangesAsync();
return RedirectToAction("Index");
}
else
{
return View();
}
}
I cannot find IdentityManager from anywhere, and context.Users doesn't have FindAsync() method either.
How can I properly delete a User and its related records in Identity 2.0?
I think the classes you're looking for are the UserManager and the RoleManager. In my opinion they are the better way instead of going against the context directly.
The UserManager defines a method RemoveFromRoleAsync which gives you the ability to remove the user (identified by his key) from a given role. It also defines several Find methods, such as FindAsync, FindByIdAsync, FindByNameAsync, or FindByEmailAsync. They all can be used to retrieve a user. To delete a user you should use the DeleteAsync method which accepts a user object as a parameter. To get the roles a user is member of Identity gives you the GetRolesAsync method where you pass in the ID of the user. Also I see that you're trying to remove a login from a user. For this purpose you should use the RemoveLoginAsync method.
All in all your code would look similar to the following one:
// POST: /Users/Delete/5
[HttpPost, ActionName("Delete")]
[ValidateAntiForgeryToken]
public async Task<ActionResult> DeleteConfirmed(string id)
{
if (ModelState.IsValid)
{
if (id == null)
{
return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
}
var user = await _userManager.FindByIdAsync(id);
var logins = user.Logins;
var rolesForUser = await _userManager.GetRolesAsync(id);
using (var transaction = context.Database.BeginTransaction())
{
foreach (var login in logins.ToList())
{
await _userManager.RemoveLoginAsync(login.UserId, new UserLoginInfo(login.LoginProvider, login.ProviderKey));
}
if (rolesForUser.Count() > 0)
{
foreach (var item in rolesForUser.ToList())
{
// item should be the name of the role
var result = await _userManager.RemoveFromRoleAsync(user.Id, item);
}
}
await _userManager.DeleteAsync(user);
transaction.Commit();
}
return RedirectToAction("Index");
}
else
{
return View();
}
}
You'll need to adjust this snippet to your needs, because I don't have an idea how your IdentityUser implementation looks like. Remember to declare the UserManager as needed. An example how you could do this can be found when you create a new project in Visual Studio using Individual Accounts.
Update for ASP.NET Core 2.0 - hope this saves someone a bit of time
ApplicationDbContext context,
UserManager<ApplicationUser> userManager,
ApplicationUser user
var logins = await userManager.GetLoginsAsync(user);
var rolesForUser = await userManager.GetRolesAsync(user);
using (var transaction = context.Database.BeginTransaction())
{
IdentityResult result = IdentityResult.Success;
foreach (var login in logins)
{
result = await userManager.RemoveLoginAsync(user, login.LoginProvider, login.ProviderKey);
if (result != IdentityResult.Success)
break;
}
if (result == IdentityResult.Success)
{
foreach (var item in rolesForUser)
{
result = await userManager.RemoveFromRoleAsync(user, item);
if (result != IdentityResult.Success)
break;
}
}
if (result == IdentityResult.Success)
{
result = await userManager.DeleteAsync(user);
if (result == IdentityResult.Success)
transaction.Commit(); //only commit if user and all his logins/roles have been deleted
}
}
Brad's point about requiring #Html.AntiForgeryToken() in views is not necessary if you are using latest versions of ASP.NET - see AntiForgeryToken still required
Why not create a SQL trigger for AspNetUsers so deleting a user also deletes the corresponding records for user from AspNetUserRoles and AspNetUserLogins?
I need to invoke DeleteUser from a number of places so I added a static method to AccountController (see below). I'm still learning about MVC, so should be grateful for comments, in particular 1) use of IdentityResult as a return code 2) wisdom of extending AccountController in this way 3) approach for putting password (cleartext) into the Model to validate the action (see sample invocation).
public static async Task<IdentityResult> DeleteUserAccount(UserManager<ApplicationUser> userManager,
string userEmail, ApplicationDbContext context)
{
IdentityResult rc = new IdentityResult();
if ((userManager != null) && (userEmail != null) && (context != null) )
{
var user = await userManager.FindByEmailAsync(userEmail);
var logins = user.Logins;
var rolesForUser = await userManager.GetRolesAsync(user);
using (var transaction = context.Database.BeginTransaction())
{
foreach (var login in logins.ToList())
{
await userManager.RemoveLoginAsync(user, login.LoginProvider, login.ProviderKey);
}
if (rolesForUser.Count() > 0)
{
foreach (var item in rolesForUser.ToList())
{
// item should be the name of the role
var result = await userManager.RemoveFromRoleAsync(user, item);
}
}
rc = await userManager.DeleteAsync(user);
transaction.Commit();
}
}
return rc;
}
Sample invocation - form passes the user's password (cleartext) in Model:
// POST: /Manage/DeleteUser
[HttpPost]
[ValidateAntiForgeryToken]
public async Task<IActionResult> DeleteUser(DeleteUserViewModel account)
{
var user = await GetCurrentUserAsync();
if ((user != null) && (user.PasswordHash != null) && (account != null) && (account.Password != null))
{
var hasher = new Microsoft.AspNetCore.Identity.PasswordHasher<ApplicationUser>();
if(hasher.VerifyHashedPassword(user,user.PasswordHash, account.Password) != PasswordVerificationResult.Failed)
{
IdentityResult rc = await AccountController.DeleteUserAccount( _userManager, user.Email, _Dbcontext);
if (rc.Succeeded)
{
await _signInManager.SignOutAsync();
_logger.LogInformation(4, "User logged out.");
return RedirectToAction(nameof(HomeController.Index), "Home");
}
}
}
return View(account);
}
I was looking also for the answer but finally this is what work well for me, even its old post but it may help for someone.
// GET: Users/Delete/5
public ActionResult Delete(string id)
{
using (SqlConnection sqlCon = new SqlConnection(connectionString))
{
sqlCon.Open();
string query = "DELETE FROM AspNetUsers WHERE Id = #Id";
SqlCommand sqlCmd = new SqlCommand(query, sqlCon);
sqlCmd.Parameters.AddWithValue("#Id", id);
sqlCmd.ExecuteNonQuery();
}
return RedirectToAction("Index");
}
// POST: Users/Delete/5
[HttpPost]
public ActionResult Delete(string id, FormCollection collection)
{
try
{
// TODO: Add delete logic here
return RedirectToAction("Index");
}
catch
{
return View();
}
}

Loop through fields of two single objects entities

[HttpPost]
public ActionResult Edit(orders neworders)
{
string modifields;
orders oldorders = HDB.orders.Where(c => c.id_order == cmd.id_order).First();
foreach (var field in oldorders)
{
if(field!= neworders.samefield)
{
modifields+=nameoffield ;
}
}
}
Q How can i compare a field from the new and from the old record and save the name of the field if the value is changed?
First() returns a single object, so can't be iterated over.
Reading between the lines it looks like you want to iterate over all the fields on the object. In that case you can use reflection to return a list of fields which you can then iterate over.
foreach (var field in oldorders.GetType().GetFields())
{
var value = field.GetValue(oldorders);
}
EDIT: from your other comments it looks like you are wanting to compare the object against another object, in which case you are better off implementing the IEquatable<T> interface. E.g.
class Order : IEquatable<Order>
{
// TODO: add properties of an Order
public string foo { get; set; }
public string bar { get; set; }
public bool Equals(Order other)
{
foreach (var field in typeof(Order).GetFields())
{
if (field.GetValue(this) != field.GetValue(other))
{
return false;
}
}
foreach (var property in typeof(Order).GetProperties())
{
if (property.GetValue(this, null) != property.GetValue(other, null))
{
return false;
}
}
return true;
}
}
An example of the Equals() method override to compare instances of the same class
public override bool Equals(object anObject)
{
if (anObject is Order)
{
Order newOrder = (Order)anObject;
if (newOrder.Name.Equals(this.Name)) //add additional comparisons as needed. You could also use a foreach loop here as Tony shows below
{
return true;
}
foreach (var field in typeof(Order).GetFields())
{
if (field.GetValue(this) != field.GetValue(newOrder)) { return false; }
}
foreach (var property in typeof(Order).GetProperties())
{
if (property.GetValue(this, null) != property.GetValue(newOrder, null)) { return false; }
}
}
return false;
}
Here's how to call in your action:
[HttpPost] public ActionResult Edit(orders neworder)
{
orders oldorder = HDB.orders.Where(c => c.id_order == cmd.id_order).First();
if(oldorder.Equals(newOrder)
{
//do wome work
}
}
I would say your orders class doesn't implement the IEnumerable interface properly. In order to use foreach in this manner you must implement the interface and at least account for all of the methods required to support it.
http://msdn.microsoft.com/en-us/library/9eekhta0.aspx
Your oldrders variable is not Enumerable. The First() method returns a sinlge object. Remove the .First() and you will have an Enumerable object which the foreach loop can use

Copy ModelState Errors to TempData & Display them In the view

Most of my action methods return PartialViews on success and RedirectToAction results on failure. For that, I would like to copy the model state errors into TempData so I could display them to the user. I've read several questions here on SO and some external links but none of them worked for me... I'm decorating the ActionMethod with ModelStateToTempData attribute from MvcContrib, then displaying it as follows in the view: (this is just a prototype)
#if (TempData.Count > 0)
{
foreach (var obj in TempData)
{
var errors = ((ModelStateDictionary)obj.Value).Values;
foreach (var error in errors)
{
<div style="position:absolute; background:Black; color:White; top:250px; left:550px;">
<span style="margin-bottom:5px; display:block; height:25px;">#error.Value</span>
</div>
}
}
}
Rather than displaying the error itself, I keep getting System.Web.Mvc.ValueProviderResult. I know this is all wrong, and eventually I would want to filter the model state errors into a dictionary inside the TempData but for now I just want to have the error string displayed in the view.
P.S: I've tried to do it manually without the MvcContrib attribute, and I got the same result. But I do prefer to use my own code so I could have more control over the whole issue.
Any suggestions?
Ok After trying a million things, I found the answer myself... :)
if (TempData["ModelErrors"] == null)
TempData.Add("ModelErrors", new List<string>());
foreach (var obj in ModelState.Values)
{
foreach (var error in obj.Errors)
{
if(!string.IsNullOrEmpty(error.ErrorMessage))
((List<string>)TempData["ModelErrors"]).Add(error.ErrorMessage);
}
}
return RedirectToAction("Index", "Home");
And in the view:
<div id="validationMessages">
#{
var errors = (List<string>)TempData["ModelErrors"];
}
#if (errors != null && errors.Count() > 0)
{
<div style="position:absolute; background:Black; color:White; top:250px; left:550px;">
#foreach (var error in errors)
{
<span style="margin-bottom:5px; display:block; height:25px;">#error</span>
}
</div>
}
</div>
UPDATE:
Here it is inside an ActionFilter:
public class CopyModelStateErrorsToTempData : ActionFilterAttribute
{
public override void OnActionExecuted(ActionExecutedContext filterContext)
{
//Only export when ModelState is not valid
if (!filterContext.Controller.ViewData.ModelState.IsValid)
{
//Export if we are redirecting
if ((filterContext.Result is RedirectResult) || (filterContext.Result is RedirectToRouteResult))
{
if (filterContext.Controller.TempData["ModelErrors"] == null)
filterContext.Controller.TempData.Add("ModelErrors", new List<string>());
foreach (var obj in filterContext.Controller.ViewData.ModelState.Values)
{
foreach (var error in obj.Errors)
{
if (!string.IsNullOrEmpty(error.ErrorMessage))
((List<string>)filterContext.Controller.TempData["ModelErrors"]).Add(error.ErrorMessage);
}
}
}
}
base.OnActionExecuted(filterContext);
}
}
I started going down this road, and then read your answer. I combined them into the following files:
TempDataDictionaryExtensions.cs
I created extension methods to do the dirty work on the TempData, because I felt it didn't belong in the Action Filter itself.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web.Mvc;
namespace Project.Web.UI.Domain
{
public static class TempDataDictionaryExtensions
{
private const string _ModelStateErrorsKey = "ModelStateErrors";
public static IEnumerable<string> GetModelErrors(this TempDataDictionary instance)
{
return TempDataDictionaryExtensions.GetErrorsFromTempData(instance);
}
public static void AddModelError(this TempDataDictionary instance, string error)
{
TempDataDictionaryExtensions.AddModelErrors(instance, new List<string>() { error });
}
public static void AddModelErrors(this TempDataDictionary instance, IEnumerable<string> errors)
{
TempDataDictionaryExtensions.AddErrorsToTempData(instance, errors);
}
private static List<string> GetErrorsFromTempData(TempDataDictionary instance)
{
object tempObject = instance.FirstOrDefault(x => x.Key == TempDataDictionaryExtensions._ModelStateErrorsKey);
if (tempObject == null)
{
return new List<String>();
}
List<string> tempErrors = instance.FirstOrDefault(x => x.Key == TempDataDictionaryExtensions._ModelStateErrorsKey).Value as List<string>;
if (tempErrors == null)
{
return new List<String>();
}
return tempErrors;
}
private static void AddErrorsToTempData(TempDataDictionary instance, IEnumerable<string> errors)
{
List<string> tempErrors;
object tempObject = instance.FirstOrDefault(x => x.Key == TempDataDictionaryExtensions._ModelStateErrorsKey);
if (tempObject == null)
{
tempErrors = new List<String>();
}
else
{
tempErrors = instance.FirstOrDefault(x => x.Key == TempDataDictionaryExtensions._ModelStateErrorsKey).Value as List<string>;
if (tempErrors == null)
{
tempErrors = new List<String>();
}
}
tempErrors.AddRange(errors);
instance[TempDataDictionaryExtensions._ModelStateErrorsKey] = tempErrors;
}
}
}
TempDataModelStateAttribute.cs
My original, copied the errors out of TempData back into ModelState prior to the ActionResult executing via OnResultExecuting. This is a combination of copying them into TempData and back out.
using System.Collections.Generic;
using System.Linq;
using System.Web.Mvc;
namespace Project.Web.UI.Domain
{
public class TempDataModelStateAttribute : ActionFilterAttribute
{
public override void OnResultExecuting(ResultExecutingContext filterContext)
{
IEnumerable<string> modelErrors = ((Controller)filterContext.Controller).TempData.GetModelErrors();
if (modelErrors != null
&& modelErrors.Count() > 0)
{
modelErrors.ToList()
.ForEach(x => ((Controller)filterContext.Controller).ModelState.AddModelError("GenericError", x));
}
base.OnResultExecuting(filterContext);
}
public override void OnActionExecuted(ActionExecutedContext filterContext)
{
if (!filterContext.Controller.ViewData.ModelState.IsValid)
{
if (filterContext.Result is RedirectResult
|| filterContext.Result is RedirectToRouteResult)
{
List<string> errors = new List<string>();
foreach (var obj in filterContext.Controller.ViewData.ModelState.Values)
{
foreach (var error in obj.Errors)
{
errors.Add(error.ErrorMessage);
}
}
((Controller)filterContext.Controller).TempData.AddModelErrors(errors);
}
}
base.OnActionExecuted(filterContext);
}
}
}
You should seriously consider this concept:
http://weblogs.asp.net/rashid/archive/2009/04/01/asp-net-mvc-best-practices-part-1.aspx#prg

How to call IValidatableObject Validate(ValdationContext) in MVC3 or include in ModelUpdate? [duplicate]

It seems that when MVC validates a Model that it runs through the DataAnnotation attributes (like required, or range) first and if any of those fail it skips running the Validate method on my IValidatableObject model.
Is there a way to have MVC go ahead and run that method even if the other validation fails?
You can manually call Validate() by passing in a new instance of ValidationContext, like so:
[HttpPost]
public ActionResult Create(Model model) {
if (!ModelState.IsValid) {
var errors = model.Validate(new ValidationContext(model, null, null));
foreach (var error in errors)
foreach (var memberName in error.MemberNames)
ModelState.AddModelError(memberName, error.ErrorMessage);
return View(post);
}
}
A caveat of this approach is that in instances where there are no property-level (DataAnnotation) errors, the validation will be run twice. To avoid that, you could add a property to your model, say a boolean Validated, which you set to true in your Validate() method once it runs and then check before manually calling the method in your controller.
So in your controller:
if (!ModelState.IsValid) {
if (!model.Validated) {
var validationResults = model.Validate(new ValidationContext(model, null, null));
foreach (var error in validationResults)
foreach (var memberName in error.MemberNames)
ModelState.AddModelError(memberName, error.ErrorMessage);
}
return View(post);
}
And in your model:
public bool Validated { get; set; }
public IEnumerable<ValidationResult> Validate(ValidationContext validationContext) {
// perform validation
Validated = true;
}
There's a way to do it without requiring boilerplate code at the top of each controller action.
You'll need to replace the default model binder with one of your own:
protected void Application_Start()
{
// ...
ModelBinderProviders.BinderProviders.Clear();
ModelBinderProviders.BinderProviders.Add(new CustomModelBinderProvider());
// ...
}
Your model binder provider looks like this:
public class CustomModelBinderProvider : IModelBinderProvider
{
public IModelBinder GetBinder(Type modelType)
{
return new CustomModelBinder();
}
}
Now create a custom model binder that actually forces the validation. This is where the heavy lifting's done:
public class CustomModelBinder : DefaultModelBinder
{
protected override void OnModelUpdated(ControllerContext controllerContext, ModelBindingContext bindingContext)
{
base.OnModelUpdated(controllerContext, bindingContext);
ForceModelValidation(bindingContext);
}
private static void ForceModelValidation(ModelBindingContext bindingContext)
{
var model = bindingContext.Model as IValidatableObject;
if (model == null) return;
var modelState = bindingContext.ModelState;
var errors = model.Validate(new ValidationContext(model, null, null));
foreach (var error in errors)
{
foreach (var memberName in error.MemberNames)
{
// Only add errors that haven't already been added.
// (This can happen if the model's Validate(...) method is called more than once, which will happen when
// there are no property-level validation failures.)
var memberNameClone = memberName;
var idx = modelState.Keys.IndexOf(k => k == memberNameClone);
if (idx < 0) continue;
if (modelState.Values.ToArray()[idx].Errors.Any()) continue;
modelState.AddModelError(memberName, error.ErrorMessage);
}
}
}
}
You'll need an IndexOf extension method, too. This is a cheap implementation but it'll work:
public static int IndexOf<T>(this IEnumerable<T> source, Func<T, bool> predicate)
{
if (source == null) throw new ArgumentNullException("source");
if (predicate == null) throw new ArgumentNullException("predicate");
var i = 0;
foreach (var item in source)
{
if (predicate(item)) return i;
i++;
}
return -1;
}

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