Today, I will show you How to Easily Add ASP.NET MVC 5 Anti-Forgery Tokens to any or all Post Requests. One of the newer attacks against web applications is that the cross-site request forgery attack. It’s an attack against modern applications that store a cookie to represent the presently logged in user. The matter has been explained in different websites.

One of the techniques to stop this attack is to add an anti-forgery token using the @Html.AntiForgeryToken extension technique. On the controller side, the action technique defines the [ValidateAntiForgeryToken] attribute. Behind the scenes, the hidden input field for the anti-forgery token is valid by the ASP.NET MVC  5 framework to confirm it’s correct. Whereas there's discussion as to whether or not this approach is required only for the logging in an anonymous posts, or all posts in general, as been up for debate. However the purpose of CSRF is to attack authenticated users.
public class GlobalAntiForgeryTokenAttribute
  : FilterAttribute, IAuthorizationFilter
{
  public sub OnAuthorization(filterContext As AuthorizationContext)
  {
                if (filterContext.HttpContext.Request.HttpMethod.ToUpper() == "POST")
                {
                  AntiForgery.Validate();
    }         
  }
}

On authorization of the request, if the operation may be a POST request, we tend to call the Validate() method on the AntiForgery helper to actually perform the validation. All of our post operations are currently checked for forgery; but, this can fail as a result of we haven’t added our token globally. To do that, we've to create a custom form extension method just like the following:

public static void FormExtensions
{
   public static MvcForm BeginDataForm(this HtmlHelper html, string action, string controller, ...)
  {
     var form = html.BeginForm(action, controller, ...);
                 //At this point, the form markup is rendered in BeginForm
                 // we can render the token       
                 //With every form, we render a token, since this
                 //assumes all forms are posts
                 html.ViewContext.Writer.Write(html.AntiForgeryToken().ToHtmlString());
                return form;
   }
}

If we use our custom helper for all of our forms, then all of our custom forms can have rendered an anti-forgery token. so we don’t have to worry about making it ourselves, saving time and reducing code.

We can do Regular Expression or REGEX validation using Annotations in ASP.NET MVC 5. we can use "RegularExpression" attribute for validation. during this attribute we specify Regular Expression string. We can also specify our custom error messages for that we'd like to set "ErrorMessage" Property in "RegularExpression" attribute. Here is the example for this.

We take "Email" Address validation using REGEX. If user enter email address, which isn't in correct format at that time our validation message display on screen.
[RegularExpression(@"[A-Za-z0-9._%+-][email protected][A-Za-z0-9.-]+\.[A-Za-z]{2,4}",
        ErrorMessage="Email Address is not in proper format.")]
        public string Email { get; set; }

At the view side , add this code:
  @Html.EditorFor(model => model.Email)
        @Html.ValidationMessageFor(model => model.Email,"", new {  style="color:red"})

Here is Code for this. Model (Customer.cs):

public class Customer
    {
        public int CustomerID { get; set; }
        [Required]
        [StringLength(20,MinimumLength=2)]
        public string FirstName { get; set; }
        [StringLength(10)]
        public string LastName { get; set; }
        [RegularExpression(@"[A-Za-z0-9._%+-][email protected][A-Za-z0-9.-]+\.[A-Za-z]{2,4}",
        ErrorMessage="Email Address is not in proper format.")]
       public string Email { get; set; }
    }

In this post we are going to update multiple row using ASP.NET MVC and Entity Framework.  Just follow these steps below:
1. First we need to create a project.
Go to Menu File > New > Project > Select ASP.NET MVC web application > Entry Application Name > Click OK.

2. Add a Database.
Go to Solution Explorer > Right Click on App_Data folder > Add > New item > Select SQL Server Database Under Data > Enter Database name > Add. 
Open Database and add a table for update operation. Here I am creating a table called Contacts.

3. Add Entity Data Model.
Go to Solution Explorer > Right Click on Project Name from Solution Explorer folder > Add > New item > Select ADO.net Entity Data Model under data > Enter model name > Add.
A popup window will come (Entity Data Model Wizard) > Select Generate from database > Next > Chose your data connection > select your database > next > Select tables > enter Model Namespace > Finish.

After Creating Data model, we have to modify our generated entity(table) for Apply validation for required fields.

Here we need to modify contact.cs fileOpen file and modify as for enable validation.
namespace UpdateMultiRecord
{
    using System;
    using System.Collections.Generic;
    using System.ComponentModel.DataAnnotations;
    public partial class Contac
  {
        [Required]        
        public int ContactID { get; set; }
        [Required]
        public string ContactPerson { get; set; }       
 [Required]
        public string Contactno { get; set; }
        public string EmailID { get; set; }
    }
}

Here I am using Home controller index action.
Get Action      
[HttpGet]
        public ActionResult Index()
        {
            List<Contact> model = new List<Contact>();
            using (MyDatabaseEntities dc = new MyDatabaseEntities())
            {
                model = dc.Contacts.ToList();
            }
            return View(model);

        }     
Post Action       
 [HttpPost]
        public ActionResult Index(List<Contact> list)
        {
           if (ModelState.IsValid)
           {
               using (MyDatabaseEntities dc = new MyDatabaseEntities())
                {
                    foreach (var i in list)
                    {
                        var c = dc.Contacts.Where(a =>                                  
                        a.ContactID.Equals(i.ContactID)).FirstOrDefault();
                        if (c != null)
                        {
                            c.ContactPerson = i.ContactPerson;
                            c.Contactno = i.Contactno;
                            c.EmailID = i.EmailID;
                        }
                    }
                    dc.SaveChanges();
                }
                ViewBag.Message = "Successfully Updated.";
                return View(list);
            }
            else
            {
               ViewBag.Message = "Failed ! Please try again.";
                return View(list);
            }
        }       
Create View for Update Multiple Row.
@model List<UpdateMultiRecord.Contact>
@{
    ViewBag.Title = "Update multiple row at once Using MVC 4 and EF ";
}
@using (@Html.BeginForm("Index","Home", FormMethod.Post))
{
    <table>
            <tr>
                <th></th>               
                <th>Contact Person</th>
                <th>Contact No</th>
                <th>Email ID</th>
            </tr>
        @for (int i = 0; i < Model.Count; i++)
        {
            <tr>               
                <td> @Html.HiddenFor(model => model[i].ContactID)</td>
                <td>@Html.EditorFor(model => model[i].ContactPerson)</td>
                <td>@Html.EditorFor(model => model[i].Contactno)</td>
                <td>@Html.EditorFor(model => model[i].EmailID)</td>
            </tr>
        }
    </table>
    <p><input type="submit" value="Save" /></p>
    <p style="color:green; font-size:12px;">
        @ViewBag.Message
    </p>
}
 @section Scripts
     {@Scripts.Render("~/bundles/jqueryval")}

Code: @Scripts.Render("~/bundles/jqueryval") will enable client side validation. Finally, Run Application. Edit Contact Details and Click Save button.

The main benefit I see in following the SPA design principles for developing rich, complex web applications is the “stateful”ness we get. For complex web application, it may be too idealistic to have just one “full” initial HTTP request to get a page, and then subsequent async calls to load further pages or data. However, we can do it module-wise i.e. certain parts of the web app follow SPA design, others may or may not follow SPA design. This is referred to as mini-spa or hybrid spa. Using AngularJs in ASP.NET MVC 6 Hosting, I have come up with a sample application which follows SPA design principles. I’m using angular route module ngRoute along with angular directive ngView to define routes – controller & view associated with each route. It is essentially MVC pattern on the client-side. Moreover, our app is now route-driven on client-side. (The browser back and fro buttons are supported)

In the sample web app, we have 2 modules. In each module, user can filter results and view/edit the record. [NOTE: using mvc music store database from CodePlex.

For each module, I've defined corresponding angular module :
ngModule musicAlbumsApp for music module
ngModule movieDvdsApp for movie module

Route configuration for music module

(function (app) {
    var routeConfig = function ($routeProvider) {
        $routeProvider.when("/", {
            controller: "musicAlbumListController",
            templateUrl: window.miniSpaApp.rootUrl + "MusicAlbums/List",
            reloadOnSearch: false
        }).when("/:genreId", {
            controller: "musicAlbumListController",
            templateUrl: window.miniSpaApp.rootUrl + "MusicAlbums/List",
            reloadOnSearch: false
        }).when("/Detail/:id", {

            controller: "musicAlbumDetailController",
            templateUrl: window.miniSpaApp.rootUrl + "MusicAlbums/Detail",
            reloadOnSearch: false        }).when("/Edit/:id", {
            controller: "musicAlbumEditController",
            templateUrl: window.miniSpaApp.rootUrl + "MusicAlbums/Edit",
            reloadOnSearch: false
        }).otherwise({ redirectTo: "/" });
    };
    routeConfig.$inject = ['$routeProvider'];
    app.config(routeConfig);
})(angular.module("musicAlbumsApp"));

Each route maps to an angular controller and a view/template. 

In our main page (MusicAlbums - Index View), we include the angular scripts and define our container div using ngView directive to load different views

@section HeadContent
{
   @Scripts.Render("~/bundles/angularMusicAlbums")
}
<div data-ng-app="musicAlbumsApp" data-ng-view="" data-ng-cloak="">
</div>

Similarly, for movie module we've defined it's route configuration and container div using ngView directive.

I have build a ASP.NET 4.5 and ASP.NET MVC 6 web app which works fine locally (IIS Express & dev server) but once I deploy it to my web server, sometimes it throws Error:

• 403.14 - Forbidden (The Web server is configured to not list the contents of this directory.)
• 404 - Not Found (The resource you are looking for has been removed, had its name changed, or is temporarily unavailable)

  

SOLUTION

• Make sure the Application pool targets correct version of .NET framework (i.e .NET Framework v4.0.30319 for .NET 4.5 and 4.5.2)
• Make sure You have setup the website as an application in IIS
• Make sure the Pipeline mode of IIS Application pool is "Integrated"
• Check UrlRoutingModule-4.0 is added in the modules of that website.
• (To do that, open list of added modules by clicking "Modules" against your website, and see if the module "UrlRoutingModule-4.0" is added or not). If not, then add a module by clicking "Add Managed Module" button, where select System.Web.Routing.UrlRoutingModule as a Module type, and give "UrlRoutingModule-4.0" as its name)
• Make sure you have following element added in system.webServer section of website's web.config

<system.webServer>
<modules runAllManagedModulesForAllRequests="true"></modules> 
</system.webServer>

In most cases of HTTP Error 403.14, or 404, above are the possible causes and fixes. 

We all know how important it is to validate user input, but it’s equally important how we present validation errors to the user. Take the following form you can see below:

The email field needs to be optional but any address entered must be valid. If a validation error occurs, it should replace the optional label with the error message. Behind the scenes I’m using Data Annotations to validate the email address, so any errors will be passed into the ModelState. ASP.NET MVC 6 has built-in support for showing these errors (using the ValidateMessageFor helper) so it’s easy to write a wrapper around that, supplying the ‘optional’ text as a parameter.

Here’s an extension method for the HtmlHelper:
public static class ExtensionMethods

{
 public static MvcHtmlString HelpMessageFor<TModel, TProperty>(this HtmlHelper<TModel> htmlHelper, Expression<Func<TModel, TProperty>> expression, string helpText)
{
        var validation = htmlHelper.ValidationMessageFor(expression);
        if (validation == null)
            return new MvcHtmlString("<span class='help-inline muted'>" + helpText + "</span>");
        else
            return validation;
    }
}

Here’s it’s usage:

<fieldset>
  <div class="control-group">
        @Html.LabelFor(x => x.EmailAddress, "Email", new { @class = "control-label" })
        <div class="controls">
            @Html.TextBoxFor(x => x.EmailAddress, new { @class = "input-xlarge", placeholder = "Enter an email address" })
            @Html.HelpMessageFor(x => x.EmailAddress, "Optional")
        </div>
    </div>
</fieldset>

Introduction

Before we start this article we will give you a quick reviews about MVC there are three parts to MVC.

Models: Part of the application that handles the application logic and contains classes representing data structure.

Views: Part of the application that handles the generation of HTML responses

Controllers: Part of the application that handles user interaction and incoming browser requests, retrieves model data and specify views

In Getting Started with Visual Studio 2013 and ASP.NET MVC 5 we created a new MVC application and took a look at some of the basics.

In this blog post we will take a look at Controllers and how they can be used

Controller in MVC

Adding a new controller The ASP.NET MVC framework maps URLs to classes that are referred to as controllers. Controllers process incoming requests, handles user input, interactions and executes appropriate application logic. A controller class typically calls a separate view component to generate the HTML mark-up for the request. The base class for all controllers is the ControllerBase class. The Controller class inherits from the ControllerBase and is the default implementation of a controller. In an MVC application, the Controller handles the following areas:

1. Locating and validating the necessary action method.
2. Getting any values used in the action method’s arguments.
3. Handling any errors that occurs.
4. Providing the deault WebFormViewEngine class for rendering views.

Using the solution we built in our previous post let’s add a new controller using these steps.

• In the Solution explorer right click on the Controllers folder, select Add and then Controller as shown in the following screenshot.

• In the Add Scaffold box select MVC 5 Controller – Empty and then click Add as shown in the following screenshot.

• In the Add Controller dialog box in the Controller name field enter TopicController and then select Add as shown in the following screenshot.

• Validate in the Solution Explorer in the Controllers folder that you have the new TopicController.cs file, in the Views folder you should also have the Topic folder as shown in the following screenshot.

** Note! there is a folder in the Views, while it is not required Views and Controllers are usually tied together. When you name a new Controller with the suffix “Controller”, Visual Studio will create the View folder automatically
In the Project explorer make sure that you have the TopicController.cs selected and in the code window replace it with the following code.

using System.Web;
using System.Web.Mvc;
 
namespace MvcMovie.Controllers
{
    public class TopicController : Controller
    {
        //
        // GET: /Topic/
 
        public string Index()
        {
            return "This is the <b>default</b> action...";
        }
 
        //
        // GET: /Topic/Welcome/
 
        public string Welcome()
        {
            return "This is the Welcome action method...";
        }
    }
}

Accessing the Controller

If the traditional ASP.NET Web Form application have user interactions organized around pages, raising and handling events from these pages and their form controls, then MVC applications are organized around controllers and action methods. A controller contains actions methods that typically have a one-to-one mapping with user interactions. For example, entering a URL into a browser causes a request to the server. The MVC application uses routing rules defined in the Global.asax file to parse the URL and to determine the path of the controller. The controller then determine the appropriate action method to call to handle the request.

By default a web request in an MVC application is treated as a sub-path that includes the controller names followed by the action name. For example is a user enters the

URL:http://www.yourdomain.com/product/category/1

The sub path evaluated is product/category/1. The default routing rule will treat product as the prefix name of the controllers (which must end in Controller). It will treat Category as the name of the action. In this case the routing rule will invoke the category method of the product controller in order to process the request. By default the value of 5 in the URL will be passed to the Detail method as a parameter.

Take a look at how this works with our application.

• Press F5 to start the application and validate that you see a similar URL as shown in the following screenshot

• Append the URL of the application with the string /Topic and then refresh the screen as shown in the following screenshot

• Append the URL of the application with the string /Topic/Welcome and then refresh as shown in the following screenshot

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In ASP.NET MVC 5.2, Customizing IDirectRouteProvider will be more easy by extending our default implementation, DefaultDirectRouteProvider. This class provides separate overridable virtual methods to change the logic for discovering attributes, creating route entries, and discovering route prefix and area prefix.

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In this article, I will write simple tutorial about detail pipeline of ASP.NET MVC.

Routing

Routing is the first step in ASP.NET MVC pipeline. typically, it is a pattern matching system that matches the incoming request to the registered URL patterns in the Route Table.

The UrlRoutingModule(System.Web.Routing.UrlRoutingModule) is a class which matches an incoming HTTP request to a registered route pattern in the RouteTable(System.Web.Routing.RouteTable).

When ASP.NET MVC application starts at first time, it registers one or more patterns to the RouteTable to tell the routing system what to do with any requests that match these patterns. An application has only one RouteTable and this is setup in the Application_Start event of Global.asax of the application.

public class RouteConfig
   {
   public static void RegisterRoutes(RouteCollection routes)
   {
   routes.IgnoreRoute("{resource}.axd/{*pathInfo}"); 

   routes.MapRoute(
   name: "Default",
   url: "{controller}/{action}/{id}",
   defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
   );
   }
   }

protected void Application_Start()
{
   //Other code is removed for clarity
   RouteConfig.RegisterRoutes(RouteTable.Routes);
}

When the UrlRoutingModule finds a matching route within RouteCollection (RouteTable.Routes), it retrieves the IRouteHandler(System.Web.Mvc.IRouteHandler) instance(default is System.Web.MvcRouteHandler) for that route. From the route handler, the module gets an IHttpHandler(System.Web.IHttpHandler) instance(default is System.Web.MvcHandler).

public interface IrouteHandler
{
   IHttpHandler GetHttpHandler(RequestContext requestContext);
}

Controller Initialization

The MvcHandler initiates the real processing inside ASP.NET MVC pipeline by using ProcessRequest method. This method uses the IControllerFactory instance (default is System.Web.Mvc.DefaultControllerFactory) to create corresponding controller.

protected internal virtual void ProcessRequest(HttpContextBase httpContext)
{
   SecurityUtil.ProcessInApplicationTrust(delegate {
   IController controller;
   IControllerFactory factory;
   this.ProcessRequestInit(httpContext, out controller, out factory);
   try
   {
   controller.Execute(this.RequestContext);
   }
   finally
   {
   factory.ReleaseController(controller);
   }
   });
}

Action Execution

1. When the controller is initialized, the controller calls its own InvokeAction() method by passing the details of the chosen action method. This is handled by the IActionInvoker.

public virtual bool InvokeAction(ControllerContext controllerContext, string actionName)

2. After chosen of appropriate action method, model binders(default is System.Web.Mvc.DefaultModelBinder) retrieves the data from incoming HTTP request and do the data type conversion, data validation such as required or date format etc. and also take care of input values mapping to that action method parameters.

3. Authentication Filter was introduced with ASP.NET MVC5 that run prior to authorization filter. It is used to authenticate a user. Authentication filter process user credentials in the request and provide a corresponding principal. Prior to ASP.NET MVC5, you use authorization filter for authentication and authorization to a user.

By default, Authenticate attribute is used to perform Authentication. You can easily create your own custom authentication filter by implementing IAuthenticationFilter.

4. Authorization filter allow you to perform authorization process for an authenticated user. For example, Role based authorization for users to access resources.

By default, Authorize attribute is used to perform authorization. You can also make your own custom authorization filter by implementing IAuthorizationFilter.

5. Action filters are executed before(OnActionExecuting) and after(OnActionExecuted) an action is executed. IActionFilter interface provides you two methods OnActionExecuting and OnActionExecuted methods which will be executed before and after an action gets executed respectively. You can also make your own custom ActionFilters filter by implementing IActionFilter.

6. When action is executed, it process the user inputs with the help of model (Business Model or Data Model) and prepare Action Result.

Result Execution

1. Result filters are executed before(OnResultnExecuting) and after(OnResultExecuted) the ActionResult is executed. IResultFilter interface provides you two methods OnResultExecuting and OnResultExecuted methods which will be executed before and after an ActionResult gets executed respectively. You can also make your own custom ResultFilters filter by implementing IResultFilter.

2. Action Result is prepared by performing operations on user inputs with the help of BAL or DAL. The Action Result type can be ViewResult, PartialViewResult, RedirectToRouteResult, RedirectResult, ContentResult, JsonResult, FileResult and EmptyResult.

3. Various Result type provided by the ASP.NET MVC can be categorized into two category- ViewResult type and NonViewResult type. The Result type which renders and returns an HTML page to the browser, falls into ViewResult category and other result type which returns only data either in text format, binary format or a JSON format, falls into NonViewResult category.

View Initialization and Rendering

1. ViewResult type i.e. view and partial view are represented by IView(System.Web.Mvc.IView) interface and rendered by the appropriate View Engine.

public interface Iview
{
   void Render(ViewContext viewContext, TextWriter writer);
}

2. This process is handled by IViewEngine(System.Web.Mvc.IViewEngine) interface of the view engine. By default ASP.NET MVC provides WebForm and Razor view engines. You can also create your custom engine by using IViewEngine interface and can registered your custom view engine in to your Asp.Net MVC application as shown below:

protected void Application_Start()
{
   //Remove All View Engine including Webform and Razor
   ViewEngines.Engines.Clear();
   //Register Your Custom View Engine
   ViewEngines.Engines.Add(new CustomViewEngine());
   //Other code is removed for clarity
}

3. Html Helpers are used to write input fields, create links based on the routes, AJAX-enabled forms, links and much more. Html Helpers are extension methods of the HtmlHelper class and can be further extended very easily. In more complex scenario, it might render a form with client side validation with the help of JavaScript or jQuery.