Wednesday, 11 March 2015

Asp.Net MVC3 And MVC4 Important Interview Questions And Answers Or Real Time MVC3 And MVC4 Interview Questions And Answers

 1) Why we are migrating from ASP.Net to MVC Framework?

Ans:
MVC design pattern is introduced for to separate the UI (User Interface) from ASP.Net.   In normal Application BL (Business Logic), DL (Data access Layer) and (PL) Presentation Layer all are combining to build the Applications. So here if you want to do modification for any one of the layer it’ll effect to all layers. It’s somewhat tedious. Regarding to this Microsoft has been introduced the MVC Framework/Application in the .Net Framework.
Model-View-Controller (MVC) has been an important architectural pattern in computer science for many years. Originally named Thing-Model-View-Editor in 1979, it was later simplified to Model-View-Controller.
2)      What is meant by MVC?
Ans:   MVC Means Model View Controller
           MVC is a design pattern for software. It is separation for those layers to manage a complex application. It means it gives the more flexibility to overall architecture that allows the change to be made to a layer, without affecting the other layers. It’s providing loose coupling between these 3 elements (Model, View, and Controller).
  The MVC separates the user interface of an application into three main aspects:
M-Model: A set of classes that describe the data you’re working with as well as the business logic for how the data can be changing and manipulating. A Model We can call as a Business Logic (Intermediate for data Exchange between Presentation Logic and Data Access Layer).
                                                            Or
These are the classes that represent the domain you are interested in. These domain objects often encapsulate data stored in a database as well as code used to manipulate the data and enforce domain-specific business logic. With ASP.NET MVC, this is most likely a Data Access Layer using a some kind of tools like ADO.NET or LINQ or Entity Framework combined with custom code containing domain-specific logic or specific domain data.
V-View: Defines how the application’s UI (User Interface) will be displayed. Its means the view of the user interface components used to display the Model data. Most of the views are created from the model data.
Or
This is a template to dynamically generate HTML. When we Creating a View Templates of Curd Operation or Else.
C-Controller: It handles the user interactions and events. Controller read data from a view, control user input and send input data to the model. It manipulates the updates that model reflect at every change of the state of an application.
Or
This is a special class that manages the relationship between the View and Model. It responds to user input, talks to the Model, and it decides which view to render (if any). In ASP.NET MVC, this class is conventionally denoted by the suffix Controller.
3)      What are the Advantages of MVC Framework?
                                     Or
What are the Benefits Of MVC Framework?
Ans :
Ø  MVC Framework is divided in 3 Components as Model (Business Logic), View (Presentation Logic) and Controller (Input Logic), which helps to Manage Complex Application.
Ø  MVC Permitting development, testing and maitainanace of each.
Ø  Its Eliminates the Problem of Load Time Delays of HTML Markup. Why because of it doesn’t use View State or Server Side Form. Complete Control over HTML output and html based.
Ø  Esaier integration with Javascript/Jquery.
Ø  Building an Internet site where HTML,Performance,and scalability are paramount ASP.NET MVC3 may be better suited.
Ø  It supports better development of Test – Driven Development Application (TDD).
Ø  Testing Becomes Very Easier and Individual UI Test also possible.
Ø  It Supports ASP.Net Routing which provides better URL (Universe Resource Locator) Mapping in Our MVC Applications. In ASP.NET routing URL can be very useful for Search Engine Optimization (SEO) and Representation State Transfer (REST).
4)      What are the Versions in MVC Framework?
Ans :
            ASP.NET 1.0 was first released in 2002. , it was easy to think of ASP.NET and Web Forms as one and the same thing. ASP.NET has always supported two layers of abstraction, though:
System.Web.UI : The Web Forms layer, comprising server controls, View State, & so on
System.Web : The plumbing, which supplies the basic web stack, including modules, handlers, the HTTP stack, and so on.
            The mainstream method of developing with ASP.NET included the whole Web Forms stack — taking advantage of drag-and-drop controls, semi-magical state fullness, and wonderful server controls while dealing with the complications behind the scenes (an often confusing page life cycle, less than optimal HTML, and so on).
            ASP.NET MVC was announced in 2007, the MVC pattern was becoming one of the most popular ways of building web frameworks.
Model-View-Controller (MVC) has been an important architectural pattern in computer science for many years. Originally named Thing-Model-View-Editor in 1979, it was later simplified to Model-View-Controller.
It has been used in dozens of frameworks since its introduction. You’ll find MVC in Java and C++, on Mac and on Windows, and inside literally dozens of frameworks.
ASP.NET MVC 1 Overview:
                                  Even before the official release, it was clear that ASP.NET MVC wasn’t your standard Microsoft product. The development cycle was highly interactive: there were nine preview releases before the official release, unit tests were made available, and the code shipped under an open source license.
All of these highlighted a philosophy that placed a high value in community interaction throughout the development process. The end result was that the official MVC 1.0 release — including code and unit tests — had already been used and reviewed by the developers who would be using it. ASP.NET MVC 1.0 was released on 13 March 2009.
ASP.NET MVC 2 Overview:
                                  ASP.NET MVC 2 was released just one year later, in March 2010. Some of the main features in MVC 2 included:    
Ø  UI helpers with automatic scaffolding with customizable templates
Ø  Attribute-based Model validation on both client and server
Ø  Strongly-typed HTML helpers
Ø  Improved Visual Studio tooling There were also lots of API enhancements and “pro” features, based on feedback from developers building a variety of applications on ASP.NET MVC 1, such as:
Ø  Support for partitioning large applications into areas
Ø  Asynchronous Controllers support
Ø  Support for rendering subsections of a page/site using Html.RenderAction
Ø  Lots of new helper functions, utilities, and API enhancements one important precedent set by the MVC 2 release was that there were very few breaking changes. I think this is a testament to the architectural design of ASP.NET MVC, which allows for a lot of extensibility without requiring core changes.
ASP.NET MVC 3 Overview:
                                         ASP.NET MVC 3 (generally abbreviated as MVC 3 from now on) shipped just 10 months after MVC 2, driven by the release date for Web Matrix. If MVC 3 came in a box, it might say something like this on the front:
Ø   Expressive Views including the new Razor View Engine!
Ø  NET 4 Data Annotation Support!
Ø  Streamlined validation with improved Model validation!
Ø   Powerful hooks with Dependency Resolution and Global Action Filters!
Ø  Rich JavaScript support with unobtrusive JavaScript, jQuery Validation, and JSON binding!
Ø  Now with NuGet!!!!
Ø  For those who have used previous versions of MVC, we’ll start with a quick look at some of these major features.
5)      What are the New Features of Asp.Net MVC 3.0?
Ans:
ü  ASP.Net MVC3 brings you the Razor View Engine (Delimiter @) with Extension of .cshtml For C# and .vbhrml For VB.
ü  An Integrated Scaffolding System Extensible Via NuGet.
ü  HTML5 Enables Project Templates.
ü  Powerful hooks With New Dependency Injection (Provides Loosely Coupling and Easily Testable and Centralize Configuration) and Global Action filter.
ü  Rich JavaScript Support(Including Unobtrusive JavaScript)
ü  JQuery Validation.
ü  JSON Binding (JavaScript Object Notation).
ü  Data Annotation support(Validating the Data for Entity Data Model or LINQ To Sql or Any data like Range attribute, Required Attribute, Regular Expression Attribute And String Length Attribute and Etc)
ü  HTML Helpers Support HTML5 Style Attributes.
6)      What is the new Razor View Engine in MVC 3.0 Framework?
Ans:
            It is designed for render the HTML Pages. When we need to include an C# or VB code with the HTML Markup within Asp.Net web pages then sometimes become very tedious. To overcome this problem Razor was implemented.
            Razor use the semantic parser to use it within the code block. It works, but it was designed to support editing controls in a graphical editor, and that legacy shows.
           
Razor view engine is a new view engine created with ASP.Net MVC model using specially designed Razor parser to render the HTML out of dynamic server side code. It allows us to write Compact, Expressive, Clean and Fluid code with new syntaxes to include server side code in to HTML.
Razor was designed specifically as a View Engine Syntax. It has one main focus: code-focused for HTML generation. Extensions of Razor View Engines are
·         .cshtml - If the programming language is C#
·         .vbhtml - If the programming language is VB
             
7)      What is the Main Function of New Razor View Engine?
Ans:
ü  It has predefined set of functions that can be used to make the coding more easily because of Razor doesn’t have the XML Like heavy syntax of the web form view engine.
ü  Razor View Engine is Very Expressive in writing Style, Compact and Fluid.
ü  It provides easy way to integrate the server code into the HTML Markup.
ü  Great IntelliSense (IntelliSense can come in handy for things like viewing the properties your model object supports).
ü  The Razor view engine’s core compilation engine has no dependencies on System.Web or ASP.NET whatever — it can be executed from unit tests, or even from the command line, So It Provides the Unit testable.
ü  Razor also simplifies markup with an improvement on the Master Pages concept — called Layouts — that is both more flexible and requires less code and that became popular and includes Spark and NHaml.
ü  Multiple views are also popular using a single application or the site as the template can be viewed using a single engine or more flexibility can be given to the use of template.
ü  Razor is used as a helper that includes all the helper methods and programming model features to synchronize with the .ASPX view engine.
ü  Razor supports many local functions with other functionalities that help in block reading and writing. It also has pre-defined set of functions that can be used to make the coding more easily.
8)      What is the Page Life Cycle of an MVC Framework?
Ans:
            The mechanism for connecting client-side events with server-side event handler code, part of the page life cycle, can be extraordinarily complicated and delicate.
·         APP INITIALIZATION: IF any of the Application is starting from the App_start() in Global.asax . It means the initiation of the application takes place that allow the application to interact the server and start to run the application and create route object in route table collection.
·         Routing: The messages are routed to the server for making the delivery of the request easier and provide the URL Mapping.
      Routing is a stand-alone component that matches incoming requests to IHttpHandlers by URL pattern. MvcHandler is, itself, an IHttpHandler, which acts as a kind of proxy to other IHttpHandlers configured in the Routes table.
·         Instantiate and Execute Controller: Initialize the request and process and execute to display output. In this The Active IControllerFactory supplies an IController Instance. It basically uses IControllerFactory to identify the controller (Developer can use different strategy to identify the Controller method and also can create custom controller by using following Contract /Interface).
Ex : public interface IController
         {
          Void Execute(ReuestContext req)
         }
·         Locate and Invoke Controller: Controller allows to locating correctly and invokes the particular action for application. The controller invokes its relevant action method, which after further processing, Calls RenderView ().The controller determines which controller method to execute, builds a list of parameters, and executes the method.
The ControllerActionInvoker object that is associated with the controller determines which action method of the controller class to call and then call’s the method. The ControllerActionInvoker gets created on the basis of the RequestContext object.
·         Instantiate and Render View: The IViewFactory supplies an IView, which pushes response data to the IHttpResponse object. This helps in view the result of the application that is being built.

HTTP Request

Routing

Controller

ViewResult

ViewEngine

View

Response
9)      Describe about the ASP.NET MVC Request Life Cycle?
Ans:
Ø  Application first receives the request & looks up the route object in RouteTable Collection. Then RouteData Object is created. In ASP.NET MVC application like normal ASP.NET application when application starts first time, it calls Application_Start() application event from Global.asax. Route table is registered(created) from Appication_Start() event.
Ø  The MVCRouteHandler object creates an instance of the MvcHandler class and passes it the RequestContext object. This is another point for creating custom handler for the handling the web Request.
Ø  MvcHandler and pass RequestContext to handler is created.
Ø  IControllerFactory from RequestContext is identified.
Ø   IControllerFactory from RequestContext is identified.
Ø  The object of class that implements ControllerBase is created.
Ø  In MyController Excute method is created.
Ø  The ControllerActionInvoker finds the action to invoke on the controller and executes that action on the controller and return to the view.
10)  How Asp.Net MVC differs from Asp.Net WebForms?
                                  Or
What is the difference between ASP.NET MVC and ASP.NET WebForms ?
Ans:
ASP.NET MVC is not a replacement for ASP.NET WebForms. Both ASP.NET MVC and ASP.NET WebForms are built on top of the Core ASP.NET Framework. In fact a lot of features we use in ASP.NET such as Roles, Membership, Authentication and a lot of namespaces, classes and interfaces can be used in an ASP.NET MVC application.
Asp.net framework is a part of .net platform for building, deploying and running web applications. Now, we can develop a web application by using Asp.Net Web Form and Asp.Net MVC.        
ASP.NET WebForms
ASP.NET MVC
Asp.Net WebForm Follow a traditional event driven development model
Asp.net MVC is a lightweight and follow MVC pattern based development model
Asp.Net Web Form has User Controls for code re-usability and is not open source.
Asp.Net MVC has Partial Views for code re-usability and is an open source.
Uses the ‘Page Controller’ pattern. Each page has a code-behind class that acts as a controller and is responsible for rendering the layout.
Uses the ‘Front Controller’ pattern. There is a single central controller for all pages to process web application requests and facilitates a rich routing architecture
Uses an architecture that combines the Controller (code behind) and the View (.aspx). Thus the Controller has a dependency on the View. Due to this, testing and maintainability becomes an issue.
ASP.NET MVC enforces a "separation of concerns". The Model does not know anything about the View. The View does not know there’s a Controller. This makes MVC applications easier to test and maintain
The View is called before the Controller.
Controller renders View based on actions as a result of the User Interactions on the UI.
At its core, you ‘cannot’ test your controller without instantiating a View. There are ways to get around it using tools.
At its core, ASP.NET MVC was designed to make test-driven development easier. You ‘can’ test your Controller without instantiating a View and carry out unit-tests without having to run the controllers in an ASP.NET process.
Asp.Net Web Form has server controls and WebForms manage state by using view state and server-based controls.
Asp.Net MVC has html helpers and ASP.NET MVC does not maintain state information by using view state
Asp.Net Web Form has file-based URLs means file name exist in the URLs must  have its physically existence
Asp.Net MVC has route-based URLs means URLs are divided into controllers and actions and moreover it is based on controller not on physical file.
WebForms supports an event-driven programming style that is like Windows applications and is abstracted from the user. The State management is made transparent by using sessions, viewstate etc. In the process, the HTML output is not clean making it difficult to manage later. The ViewState also increases your page size.
In ASP.NET MVC, the output is clean and you have full control over the rendered HTML. The orientation is towards building standard compliant pages and provides full control over the behavior of an application.
Deep understanding of HTML, CSS and JavaScript is not required to a large extent since the WebForm model abstracts a lot of these details and provides automatic plumbing. While abstracting details to provide ease of use, sometimes a solution is overcomplicated, than it needs to be.
A thorough understanding of how HTML, CSS and JavaScript work together is required. The advantage is you can do a lot of jQuery and AJAX stuff in an efficient and simple manner than you would do in an ASP.NET application.
WebForms can drastically reduce time while building up intranet and internet applications that use a lot of controls (drag and drop model). Although this is true for development, a lot of time is spent later to code around limitations.
You lose the 'drag and drop' quick model of building your web applications. The focus is on control over the application behavior and test-driven development. The model is extensible and you do not have to spend time working around limitations.
Relatively simple to learn and pickup. Works very well for developers who initially have trouble with the HTTP/HTML model and are coming from a similar WinForms oriented event model.
There is a learning curve to understand the why, when and how of ASP.NET MVC.
Lesser amount of code is required to build webapps since a lot of components are integrated and provided out of the box. You can also use a lot of data controls provided out of the box that rely on ViewState.
Since the application tasks are separated into different components, amount of code required is more. Since ASP.NET MVC does not use ViewState, you cannot use Data controls like GridView, Repeater.
Works very well for small teams where focus is on rapid application development.
Works well for large projects where focus in on testability and maintainability.
11)  How Asp.Net MVC Framework differs from others?
Ans:
  Ø  Asp.Net  MVC uses a complete Model-View-Controller Architecture that combines the Controller and thye view in a way that both meets the dependency of each other and provides loose coupling between these 3 elements.
 Ø  In many Web Frameworks such as ASP,JSP,PHP and ASP.NET,The URL represents a Physical file on disk.In MVC doesn’t necessarily mean a physical location of a static file on a web server’s hard drive somewhere; it mose certainly doesn’t in the case of ASP.NET MVC.
  Ø  The testing of the architecture can be done by instantiating a View and carrying out the unit tests without running the controller through the complete cycle.

 Ø  The Control of MVC on the output is complete and it renders the HTML in a very clean way and it controls the delay of page load.
 Ø  In MVc the Scaffolding Templates Curd Operation is full worthy component based in MVC Framework,but JSP is a barebones view technology & Servlet is just a barebones HTTP Controller API and Comparison of Scaffloding plug-in in JSF.

Ø  The MVc Architecture Provides an orientation towards the standard complaint pages and control over the behavior of the applications

Ø  the knowledge of many programming language gets reduced and the model can become more abstract from lots of details that is provided for the ease of use.

Ø  MVC is not a language for frontend and backend with a language like PHP or C#/VB.Net and to get parsed by the Server(PHP,C#/VB) and a languages markups get parsed by the client browsers(JavaScript/JQuery/HTML/CSS) and you can Mix the two and Parse to Server.So it’s the open source for .Net.
12)  Explain the ASP.NET MVC Folder Conventions?
Ans:
Folder or File                                Description                                                                 Notes
/App_Data               This directory is where you put private        IIS will not serve the contents of
                                  data, such as XML files or databases             this directory.
                                  if you are using SQL Server Express,
                                  SQLite, or other file-based repositories.
/bin                           The compiled assembly for your MVC       IIS will not serve the contents of                                      
                                   application is placed here,along with        this directory. You won’t see the 
                                   any referenced assemblies that are           bin directory in the solution
                                   not in the GAC.                                              explorer window unless you click
                                                                                                           the Shows all Files button. these are
                                                                                                        binary files generated on compilation,
                                                                                                         you should not normally store them
                                                                                                        in source control.
/Content                 This is where you put static content      This is a convention but not required.
                                  such as CSS files and images.                  You can put your static content
                                                                                                       anywhere that suits you.
/Controllers           This is where you put your controller      This is a convention. You can put your
                                classes.                                                           controller classes anywhere you like,
                                                                                                       because they are all compiled into the
                                                                                                       same assembly.
/Models                 This is where you put your view               This is a convention. You can define
                               model and domain model classes,            your model classes anywhere in the
                              although all but the simplest appl              project or in a separate project.
                              benefit from defining the domain
                              model in a dedicated project, as we
                              demonstrated for Sports Store.
/Scripts             This directory is intended to hold the         This is a convention. You can put script
                            JavaScript libraries for your appl.               files in any location, as they are really
                           Visual Studio adds the libraries for            just another type of static content.
                         jQuery and Microsoft AJAX helpers by default.
/Views           This directory holds views and partial        The /Views/Web.config file prevents IIS
                       Views, usually grouped together in              from serving the content of these
                       Folders named after the controller              directories. Views must be rendered
                       With which they are associated.
13)  Explain the Namespace Classes used in ASP.Net MVC?
Ans:       
            Asp.Net MVC uses the namespace classes that as follows
System.Web.Mvc namespace 
Contains classes and interfaces that support the MVC pattern for ASP.NET Web applications. This namespace includes classes that represent controllers, controller factories, action results, views, partial views, and model binders.
System.Web.Mvc.Ajax namespace 
Contains classes that support Ajax scripts in an ASP.NET MVC application. The namespace includes support for Ajax scripts and Ajax option settings.
System.Web.Mvc.Async namespace 
Contains classes and interfaces that support asynchronous actions in an ASP.NET MVC application. The Goal of the asynchronous Classes in controllers to provide better scalability, especially for complex calculations that take long which are accessed by many simultaneous users.
System.Web.Mvc.Html namespace 
Contains classes that help render HTML controls in an MVC application. The namespace includes classes that support forms, input controls, links, partial views, and validation.
Every Views inherits an Html property from its base class. All of MVC’s extension methods for
HtmlHelper live in the System.Web.Mvc.Html namespace.

14)  Can you add the own Namespaces in ASP.Net MVC and How?
Ans: 
       Yes, You can add your own namespaces i.e Custom Namespaces and Look Like this
<add namespace="My.Custom"/>
  So it'll add the namespace to all of .Cshtml in C# and .Vbhtml in VB files and also you can chnage Views and you can access for only one view look like this
<pages pageBaseType = "My.Custom.MVCWebPage />

For Example:
<pages pageBaseType= “System.Web.Mvc.WebViewPage”>
<namespaces>
<add namespace=”MyCustomNamespace”/>
</namespaces>                
<pages>

15)  What are the return type’s controller action methods supports in ASP.NET MVC?
Ans:
            There are total nine return types we can use to return results from controller to view. The base type of all these result types is ActionResult.
Controller Convenience Methods That Return ActionResult Instances
1.      RedirectResult (Redirect): Used to redirect to another controller and action method based on a URL and return appropriate URL.
2.      RedirectToRouteResult(RedirectToAction): Returns a RedirectToRouteResult, which redirects the user to an action using the supplied route values.
3.      RedirectToRouteResult (RedirectToRoute): Returns a RedirectToRouteResult, which redirects the user to the URL that matches the specified route values.
4.      ViewResult (View): Returns a ViewResult, which renders the View to the response. Used to return a webpage from an action method.
5.      PartialviewResult(PartialView):  Returns a PartialViewResult, which renders a partial View to the response. Used to send a section of a view to be rendered inside another view.
6.      ContentResult (Content): Returns a ContentResult, which writes the specified content (string) to the response. It means used to return a custom content type as the result of the action method. This is an HTTP content type, such as text/plain.
7.      FileResult (File): Returns a class that derives from FileResult, which writes binary content to the response.
8.     JsonResult (Json): Returns a JsonResult containing the output from serializing an object to JSON. It means used to return a message formatted as JSON.
9.     JavascriptResult (Javascript): Returns a JavaScriptResult containing JavaScript code that is immediately executed when returned to the client. It means used to return JavaScript code that will be executed.
16)  How to create an Action method in Asp.Net MVC?
Ans: 
          Add a simple method inside a Controller class with ActionResult return type.             
17)  What is the default Form Method (i.e. Get or Post) for an Action method in Asp.Net MVC?
Ans:
            GET. To change this you can add an action level attributes e.g(HttpPost)
18)  What are the return type’s controller action results types to perform the methods in ASP.NET MVC?
Ans:
ACTIONRESULT TYPE
DESCRIPTION
ContentResult
Writes the specified content directly to the response as text.
EmptyResult
Represents a null or empty response. It doesn’t do anything.
FileContentResult
Derives from FileResult and writes a byte array to the response.
FilePathResult
Derives from FileResult and writes a file to the response based on a file path.
FileResult
Serves as the base class for a set of results that writes a binary response to the stream. Useful for returning files to the user.
FileStreamResult
Derives from FileResult and writes a stream to the response.
HttpNotFound
Derives from HttpStatusCodeResult. Returns an HTTP 404 response code to the client, indicating that the requested resource is not found.
HttpStatusCodeResult
Returns a user-specifi ed HTTP code
HttpUnauthorizedResult
Derives from HttpStatusCodeResult. Returns an HTTP 401 response code to the client, indicating that the requestor does not have authorization to the resource at the requested URL.
JavaScriptResult
Used to execute JavaScript code immediately on the client sent from the server.
JsonResult
Serializes the objects it is given into JSON and writes the JSON to the response, typically in response to an Ajax request.
PartialViewResult
This is similar to ViewResult, except it renders a partial View to the response, typically in response to an Ajax request.
RedirectResult
Redirects the requestor to another URL by returning either a temporary redirect code 302 or permanent redirect code 301 depending upon a Boolean Permanent flag.
RedirectToRouteResult
Similar to RedirectResult, but redirects the user to a URL specified via Routing parameters.
ViewResult
Calls into a View engine to render a View to the response.

19)  What is Action Filters in Asp.Net MVC?
Ans:
Action filters (locating and injecting filters)
                It’s applied for pre and or processing logic to controller action. Its uses to cross putting logic to your application. MVC Action filters gave you hooks to execute code before or after an action method ran. They were implemented as custom attributes that could be applied to controller actions or to an entire controller. This is especially useful for application infrastructure concerns like error handling and logging.
Once an action method has been selected, the action is then executed, and if it returned a result, the result is then executed. Action filters allow the developer to participate in the action and result execution pipeline in four ways: for authorization, for pre- and post-processing of actions, for pre- and post-processing of results, and for error handling.
Action filters can be written as attributes that are applied directly to the action methods (or controller classes), or as standalone classes that are registered in the global filter list. If you intend to use your action filter as an attribute, it must derive from FilterAttribute (or any subclass, such as ActionFilterAttribute). A global action filter that is not an attribute has no base class requirements. Regardless of which route you take, the filtering activities you support are determined by the interfaces you implement.
20)  Describe the different types of Action Filters in ASP.NET MVC?
Ans:
            There are mainly three types of action filters provided in ASP.NET MVC.

Authorization Filter: It makes security decisions about whether to execute an action method, such as performing authentication or validating properties of the request. Authorization filters execute very early in the action pipeline, so they’re appropriately.
          It is used for activities that short circuit the entire action execution. TheAuthorizeAttribute class is one example of an authorization filter.

Action and Result Filter: An action filter that wants to participate in pre- and post-processing of actions should implement the IActionFilter interface. This interface offers two methods to implement: OnActionExecuting(for pre-processing) and OnActionExecuted (for post-processing). Similarly, for pre- and post processing of results, an action filter should implement IResultFilter, with its two filter methods:OnResultExecuting and OnResultExecuted.
It wraps execution of the ActionResult object. This filter can perform additional processing of the result, such as modifying the HTTP response. TheOutputCacheAttribute class is one example of a result filter.

Execution Filter: It executes if there is an unhandled exception thrown somewhere in action method, starting with the authorization filters and ending with the execution of the result. Exception filters can be used for tasks such as logging or displaying an error page. The HandleErrorAttribute class is one example of an exception filter.

Apart from the readymade action filters provided by ASP.NET MVC, you can also implement your own action filter by inheriting ActionFilterAttribute abstract class. It has four virtual methods that you can override: OnActionExecuting, OnActionExecuted, OnResultExecuting and OnResultExecuted. To implement an action filter, you must override at least one of these methods.
Developers often use exception filters to perform some sort of logging of the errors, notification of the system administrators, and choosing how to handle the error from the end user’s perspective (usually by sending the user to an error page)
21) Give an Example for Authorization Filtes in an Asp.Net MVC Application ? 
Ans: 
         1. ReuireHttpsAttribute
         2. AuthorizeAttribute
22 Give an Example for Result Filters in an Asp.Net MVC Application ? 
Ans: 
          OutputCacheAttribute

23 Which Filters Excutes First in an Asp.Net MVC Application ? 

Ans: 
           Authorization filter

24 Which filters are executed in the end ?
Ans: 
           Exception Filters

25)  What are The HTML Helpers in ASP.NET MVC?
Ans:
            Every Razor view inherits an Html property from its base class. The Html property is of type System.Web.Mvc.HtmlHelper.
            In MVC, HTML Helpers are much like traditional ASP.NET web form controls. Just like web form controls in ASP.NET, HTML helpers are used to modify HTML. But HTML helpers are more lightweight. Unlike Web Form controls, an HTML helper does not have an event model and a view state. In most cases, an HTML helper is just a method that returns a string. With MVC, you can create your own helpers, or use the built in HTML helpers. MVC includes standard helpers for the most common types of HTML elements, like HTML links and HTML form elements.To name a few there is BeginForm(), EndForm(), TextBox(), TextArea(), ListBox(), RadioButton(), etc.
Detailed Description:

The MVC Templated HTML Helpers
Helper
Example
Description
Display
Html.Display("FirstName")
Renders a read-only view of the specified model property, choosing an HTML element according to the property’s type and metadata
DisplayFor
Html.DisplayFor(x =>x.FirstName)
Strongly typed version of the previous helper
Editor
Html.Editor("FirstName")
Renders an editor for the specified model property, choosing an HTML element according to the property’s type and metadata
EditorFor
Html.EditorFor(x =>x.FirstName)
Strongly typed version of the previous helper
Label
Html.Label("FirstName")
Renders an HTML <label> element referring to the specified model property
LabelFor
Html.LabelFor(x => x.FirstName)
Strongly typed version of the previous helper
DisplayText
Html.DisplayText("FirstName")
Bypasses all templates and renders a simple string representation of the specified model property
DisplayTextFor
Html.DisplayTextFor(x =>
x.FirstName)
Strongly typed version of the previous helper
The MVC Scoffolding Templated HTML Helpers
Helper
Example
Description
DisplayModelFor
Html.DisplayModelFor ()
Renders a read-only view of the entire model object
EditorForModel
Html.EditorForModel()
Renders editor elements for the entire model object
LabelForModel
Html.LabelForModel()
Renders an HTML <label> element referring to the entire model object
26)  What is Routing?
Ans:
            A route is a URL pattern that is mapped to a handler. The handler can be a physical file, such as an .aspx file in our web application. Routing module is responsible for mapping incoming browser requests to particular MVC controller actions.
When you create a new ASP.NET MVC application, the application is already configured to use ASP.NET Routing. ASP.NET Routing is setup in two places.
First, ASP.NET Routing is enabled in your application's Web configuration file (Web.config file). There are four sections in the configuration file that are relevant to routing: 
1)      the system.web.httpModules section,
2)       the system.web.httpHandlers section,
3)       the system.webserver.modules section, and
4)       the system.webserver.handlers section.
Be careful not to delete these sections because without these sections routing will no longer work.
Second, and more importantly, a route table is created in the application's Global.asax file. The Global.asax file is a special file that contains event handlers for ASP.NET application lifecycle events. The route table is created during the Application Start event.
27)   How you define the routing system and describe?
Ans:
                Every ASP.NET MVC application needs at least one route to define how the application should handle requests but usually will end up with a handful or more. It’s conceivable that a very complex application could have dozens of routes or more.
You’ll see how to define routes Route definitions start with the URL pattern, which specifies the pattern that the route will match. Along with the route URL, routes can also specify default values and constraints for the various parts of the URL, providing tight control over how and when the route matches incoming request URLs. Routes can also have names which are associated with the route when that route is added to a route collection. We’ll cover named routes a bit later.
Ex :
public static void RegisterRoutes(RouteCollection routes)
{
routes.MapRoute(“JaganContoller”, “{first}/{second}/{third}”);
}
public static void RegisterRoutes(RouteCollection routes)
{
routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
routes.MapRoute(
"Default", // Route name
"{controller}/{action}/{id}", // URL with parameters
new { controller = "MVC", action = "ListOfQuestions", id = UrlParameter.Optional }
);
The ASP.NET routing system is used by MVC to handle incoming requests from clients, but it also requests outgoing URLs that conform to our URL scheme and that we can embed in web pages. This way, we make sure that all of the URLs in the application are consistent.
Generate outgoing  URLs. These are the URLs that appear in the HTML rendered
from our views so that a specific action will be invoked when the user clicks the
link (at which point, it has become an incoming URL again).
we will focus on defining routes and using them to process incoming
URLs so that the user can reach your controllers and actions. Then we’ll show you how to use those same routes to generate the outgoing URLs you will need to include in your HTML.

28)  How route table is created in asp.net mvc?
Ans: When an MVC Application first start, The Application_start() method is called.This method,in turn, calls the RegisterRoutes() method.The RegisterRoutes() method creates the route table object in route table collection.
29 What is the difference between adding routes, to a webform application and to an MVC application ?

Ans: To add routes to a webform application, we use MapPageRoute() method of the RouteCollection class, where as to add routes to an MVC appilication we use MapRoute method().      
30)  What are the 3 things that are needed to specify name?
Ans:
1.      URL Pattern - You can include placeholders in a URL pattern so that variable data can be passed to the request handler without requiring a query string.
2.       Handler - The handler can be a physical file such as an .aspx file or a controller class.
3.      Name for the Route - Name is optional.
31)  What are 3 segments of the default route, which is present in an ASP.NET MVC application?
Ans: 
1st Segment - Controller Name(Route Name)
2nd Segment - Action Method Name
3rd Segment - Parameter that is passed to the action method
         
routes.MapRoute(
 "Default", // Route name
"{controller}/{action}/{id}", // URL with parameters
 new { controller = "Home", action = "Index", id = UrlParameter.Optional } // Parameter defaults );
32)  What is the use of the following default route?
Ans:
{resource}.axd/{*pathInfo}
This route definition, prevent requests for the Web resource files such as WebResource.axd or ScriptResource.axd from being passed to a controller.
33)  Where the routing rules are defined in an asp.net MVC application?
Ans:
            When application start,The Appilication_start event occurred and RegisterRoutes value will be defined in Global.aspx
34)  Is the following route definition a valid route definition?
Ans:
            {controller}{action}/{id}
No, the above definition is not a valid route definition, because there is no literal value or delimiter between the placeholders. Therefore, routing cannot determine where to separate the value for the controller placeholder from the value for the action placeholder.
35)  How do you handle variable number of segments in a route definition?
Ans:
            Use a route with a catch-all parameter. An example is shown below. * is referred to as catch-all parameter.
controller/{action}/{*parametervalues}
36)  What are the 2 ways of adding constraints to a route?
Ans:
1.       Use regular expressions
2.      Use an object that implements IRouteConstraint interface
37)  Give 2 examples for scenarios when routing is not applied?
Ans:
1.      A Physical File is Found that Matches the URL Pattern - This default behaviour can be overriden by setting the RouteExistingFiles property of the RouteCollection object to true.
2. Routing Is Explicitly Disabled for a URL Pattern - Use the RouteCollection.Ignore() method to prevent routing from handling certain requests.
38)  What is Data Annotations?
Ans:
            The MVC Framework can perform client-side validation based on the data annotations we applied to the domain model class.  
Data Annotations are validation mechanism we can use to validate our data stored in form of Entity Data Model, LINQ to SQL or any other data models. We can use it in form of attributes to our properties of mode class. These attributes provide common validation patterns, such as range checking and required fields. Once we apply these attributes to our model class, ASP.NET MVC will provide both client and server side validation checks with no additional coding required. You can also implement your custom Data Annotation Validator by inheriting ValidationAttribute class and overriding IsValid method. To name a few there is RangeAttribute, RequiredAttribute, StringLengthAttribute, RegularExpressionAttribute, etc.
The core library provides server-side validation attributes that can be used in any .NET 4.0 project (no MVC dependency). There is also an easily pluggable client-side validation library which can be used in ASP.NET MVC 3 projects using unobtrusive jquery validation (only MVC3 included javascript files are required).
Validation of user input is integral to building a modern web application, and ASP.NET MVC offers us a way to enforce business rules on both the client and server using Model Validation.  The recent release of ASP.NET MVC 3 has improved these offerings on the client side by introducing an unobtrusive validation library built on top of jquery.validation. Out of thebox MVC comes with support for Data Annotations (that is, system.ComponentModel. DataAnnotations) and can be extended to support other frameworks.  Data Annotations Validation is becoming more popular and is being baked in to many other Microsoft offerings, including Entity Framework, though with MVC it only contains four validators: Range, Required, StringLength and Regular Expression.  The Data Annotations Extensions project attempts to augment these validators with additional attributes while maintaining the clean integration Data Annotations provides.
39)  Is it possible to combine ASP.NET webforms and ASP.MVC and develop a single web application?
Ans:
            Yes, it is possible to combine ASP.NET webforms and ASP.MVC and develop a single webapplication.
40)  Which approach provides better support for test driven development - ASP.NET MVC or ASP.NET Webforms?
Ans: ASP.NET MVC
41)  Is it possible to unit test an MVC application without running the controllers in an ASP.NET process?
Ans:
            Yes, all the features in an asp.net MVC application are interface based and hence mocking is much easier. So, we don't have to run the controllers in an ASP.NET process for unit testing.
42)  Is it possible to share a view across multiple controllers?
Ans:
            Yes, put the view into the shared folder. This will automatically make the view available across multiple controllers.
43)  What is the significance of NonActionAttribute?
Ans:
            In general, all public methods of a controller class are treated as action methods. If you want prevent this default behaviour, just decorate the public method with NonActionAttribute.
44)  What symbol would you use to denote, the start of a code block in razor views?
Ans:
            @
45)  What symbol would you use to denote, the start of a code block in aspx views?
Ans:
            <%=%>
46)  In razor syntax, what is the escape sequence character for @ symbol?
Ans:
            The escape sequence character for @ symbol, is another @ symbol
47)  When using razor views, do you have to take any special steps to protect your asp.net mvc application from cross site scripting (XSS) attacks?
Ans:
            No, by default content emitted using a @ block is automatically HTML encoded to protect from cross site scripting (XSS) attacks.
48)  When using aspx view engine, to have a consistent look and feel, across all pages of the application, we can make use of asp.net master pages. What is asp.net master pages equivalent, when using razor views?
Ans:
            To have a consistent look and feel when using razor views, we can make use of layout pages. Layout pages, reside in the shared folder, and are named as _Layout.cshtml.
49)  How do you specify comments using razor syntax?
Ans:
            Razor syntax makes use of @* to indicate the begining of a comment and *@ to indicate the end. An example is shown below.
50)  What are sections?
Ans:
            Layout pages, can define sections, which can then be overriden by specific views making use of the layout. Defining and overriding sections is optional.
51)  What is Repository Pattern in ASP.Net MVC?
Ans:
            The Repository will delegate to the appropriate infrastructure services to get the job done.It uses mechanism of encapsulating that storage, retrieval & query for the implementation of the repository.
 It allows easy testing in the form of unit testing & mock testing.
Repository pattern is used as a default entity operation that allows the decoupling of the components used for presentation.
Repository pattern will have the proper infrastructure services to be used in the web applications.
Repository patterns are hard coded in the application that is to be used in ASP.NET MVC architecture. 
52)  What is difference between TempDate and ViewData and ViewBag Pattern in ASP.Net MVC?
Ans:
            TempData :
·         TempData is also a dictionary derived from TempDataDictionary class and stored in short lives session and it is a string key and object value.
·         TempData keep the information for the time of an HTTP Request. This mean only from one page to another.
·          It requires typecasting for complex data type and check for null values to avoid error.  It’s used to store one time messages like error messages,validation messages.
·         Helps to maintain data when you move from one controller to other controller or from one action to other action. In other words when you redirect, “Tempdata” helps to maintain data between those redirects. It internally uses session variables.
·         It’s life is very short and lies only till the target view is fully loaded.
            ViewData :
·         ViewData is a dictionary object that you put data into, which then becomes available to the view.
·         ViewData is a derivative of the ViewDataDictionary class, so you can access by the familiar "key/value" syntax.
·         ViewData is used to pass data from controller to corresponding view.
·         Its required typecasting for complex data type and check for null values to void error.
·         Its life lies only during the current request.
·         If redirection occurs then it’s value becomes null.
·         Helps to maintain data when you move from controller to view.
ViewBag :
·         ViewBag is a dynamic property that takes advantage of the new dynamic features in C# 4.0.
·         ViewBag doesn’t require typecasting for complex data type.
·         Viewbag is used to pass data from controller to corresponding view.
·         Helps to maintain data when you move from controller to view.
·         It’s life aslo lies only during the current request.
Note :  TempData need more verification to never have any confidential information. Regarding ViewData or ViewBag you should use it intelligently for application performance. Because each action goes through the whole life cycle of regular asp.net mvc request. You can use ViewData/ViewBag in your child action but be careful that you are not using it to populate the unrelated data which can pollute your controller.
ViewData VS ViewBag VS TempData
 
     ViewData
      ViewBag
     TempData
It is Key-Value Dictionary collection
It is a type object
It is Key-Value Dictionary collection
ViewData is a dictionary object and it is property of ControllerBase class
ViewBag is Dynamic property of ControllerBase class.
TempData is a dictionary object and it is property of controllerBase class.
ViewData is Faster than ViewBag
ViewBag is slower than ViewData
NA
ViewData is introduced in MVC 1.0 and available in MVC 1.0 and above
ViewBag is introduced in MVC 3.0 and available in MVC 3.0 and above
TempData is also introduced in MVC1.0 and available in MVC 1.0 and above.
ViewData  is also work with .net framework 3.5 and above
ViewBag  is only  work with .net framework 4.0 and above
TempData  is also work with .net framework 3.5 and above
Type Conversion code is required while enumerating
In depth, ViewBag is used dynamic, so there is no need to type conversion while enumerating.
Type Conversion code is required while enumerating
It value become null if redirection is occurred.
Same as ViewData
TempData is used to pass data between two consecutive requests.
It lies only during the current request.
Same as ViewData
TempData is only work during the current and subsequent request
53)  What are the areas in mvc?
Ans:
            Controllers should only be responsible for interacting with views. That is, instantiating and populating model objects, retrieving data from your business objects or data access layer, responding to any requests from the page (form submissions, AJAX requests, interface to dynamic resource creation methods/classes (such as creating CAPTCHAs or other dynamic images)), etc. If you stick to that philosophy, their size and complexity should never exceed that of your views.
Areas I tend to use areas to break up the application into sub-applications. For instance, a site may have a discussion forum, Employee Category, Department Category, Company information, support database, etc, all of which would be separate areas:
/areas/Employee
/areas/Department
/areas/Support
/areas/CompanyInfo
Then, in each area,U might have some methods
/areas/Employee/{Views|Controllers}
/areas/Employee/EmployeeList
/areas/Employee/EmployeeContactList
etc
Just as in a webforms site where each folder represented a distinct "area" of the website, areas provide another level of organization that lets you keep related controllers, views, etc in a common location, and should be used in a similar fashion.
We use areas to distinguish notable separate concerns within the application. Especially separate concerns that may require unique authentication or layout/styling for each area.
For example, I'm working on an application that has "modules" of sorts. Each module is an mvc area and each module as a setup section that is also an mvc area. The application has three modules, so that is a total of six areas -- with six user rights to go along with them. This allows each module to have a new "master page/layout" (appearance) and a specific security level.
It helps in separating the code as well; code in Areas has nothing to do with code in AreaB, but sometimes AreaA and AreaB use common code found in the root of the project.
The non-area parts of the site have things like the user-login, error pages (404, etc), the main "launcher" area to enter the modules, exception handing, and other encompassing things that cross-cut across any of the mvc areas.
54)  Whether  Razor Views  are Precompiled Or not ? and What is the use of precomilation of Views?
Ans:
            By Default, the operating of  Comiling a Razor view is close enough to that used by WebForms Views.This Means that processes and compiles the views of an ASP.NET MVC Application as late as possible,it is called JIT(Just In Time).As late as possible" meaning when a reply using the view in question must be returned to a client. Once this stage of compilation is complete, the result is cached in the temporary directory of the IIS site, and future clients accessing this resource will not cause a new compilation.
Obviously, the time of compilation of views will now be passed on to the position of each developer on the team. A hybrid solution would be to compile the views, nor at runtime or on the position of each developer, but during the compilation process of continuous integration.
One Reason used by precompilation than at runtime compilation.You no longer need to deploy the cshtml views at all.and ability to unti test your views ,which has always been something very difficult with standard runtime compilation model.
55)  What is  Globalization and Internationalization and Localization in ASP.NET MVC3 ?
Ans:
            Internationalization :  Making your application able to support a range of languages and locales. It involves Globalization and Localization.
            Globalization The processing of making an application for a given language and regions (culture).
            Localization : Making your application support a specific language/localizable format.
Note :  Some of the companies said Like IBM and Microsystems, use the term “Globalization” for the combination of internationalization and localization. As i described according Microsoft.
56)  What is  JSON Hijacking in ASP.NET MVC3 and How will you use JSON Hijacking?
Ans:
            Json stands for javascript object notation which is used to interchange data between various languages a typical example is any server side language like c#,vb.net with Javascript. 
whenever you make an Ajax Call to retrieve some sort of data then the best format to retrieve data is Json which is string:value pair.
IF any request has been blocked means  sensitive information could be disclosed to third party web sites when this is used in a GET request. To allow GET requests, set JsonRequestBehavior to AllowGet.

Its because Json only allow Json Post(as its more secure) Request but deny Get request because confidential information can not be retrieve using get request.
JSON (pronounced like the English name, Jason) hijacking is a rare hack similar to XSRF, except it’s targeted to request secure JSON from vulnerable applications. The JSON hijacking process involves several steps:
1. A conspiring site, via JavaScript, instructs the victim’s browser to request some secure JSON data from another site.
2. The evil JavaScript receives the JSON data.
3. If the JSON is formatted as an array, the evil script can exploit browser JavaScript processing code to read the JSON data and transmit it back to the attacking site.
Solution For JSON Hijacking :

            Allow JSON via POST only  The solution to this exploit offered by ASP.NET MVC 2 is to only accept requests for JSON data by HTTP POST requests, rather than by GETs. This is baked into and enforced by the standard JsonResult action result that ships with the framework. If we were to request data to be returned by JsonResult with a GET request, we wouldn’t receive the JSON data.

Implementing data in JSON response array by exposing sensitive data. when returning JSON response array. Add [AcceptVerbs(HttpVerbs.Post)] to make it http request return response type.(Cross Site Request Forgery (CSRF) attackk ) or XSRF.

I faced So many Interviews and Real Time Experience in MVC3. I Hope These all interview questions and answers Help full for mostly  Experienced and Freshers.
Thanks & Regards
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