The most sensitive and challenging time for a developer is interview time. If you are preparing for an ASP.NET MVC Interview Questions, you should know the top questions and answers of ASP.NET MVC that we listed below after significant research in the software industry.
1. What is MVC?
MVC stands for Model View Controller. MVC was designed in 1970 and widely adopted on the web. It is a framework/architecture to build applications efficiently. As you can understand by its name MVC contains three portions/layers Model, View and Controller.
Now the question is, what is Model View Controller.
Model handles the data logic of the application. It contains the application’s data objects that interact with the database that we use to manipulate the database record.
View handles data presentation. It is the User-Interface of the Application. Like View is the layer that the user interacts with.
Controller is the portion that receives input from the user and update/change the Model records, and return the updated response to the View. The controller handles request flow from the user. It Never takes data logic.
The View means that the presentation of data and the logic of data are entirely separated, making creating complex applications much easier this is all just theoretical, though.
Example:
So let’s look at an example of how this design handles a request imagine a user sends a request to a server to get a list of cats the server would send that request to the Controller that handles cats. The Controller asks the model that handles cats to return a list of all cats, the model would query the database for a list of all cats and return back that list to the controller.
If the response from the model was successful then the controller would ask the View associated with cats to return the presentation of the list of cats. This View would take the list of cats from the Controller and render it into HTML that could be used by the browser.
The Controller would take that presentation and return it back to the user thus ending the request if earlier the model returned an error instead of a list of cats. The Controller would handle that error by asking the View about the presentation of the error.
As we can see from that example the model handles all of the data, the View handles all of the presentations, and Controller just tells the mod what to do.
2. What is ASP.NET?
ASP.NET is a server-side technology used for developing dynamic web applications. ASP.NET was released in 2002 and had an extension of .aspx. It produces interactive, data-driven web applications on the internet.
3. What is ASP.NET MVC?
ASP.NET is based on ASP.NET Framework. It is an alternative to web forms for developing web applications.
4. What is the MVC application life cycle?
In general terms, the life cycle is the set of certain stages that occur at a certain time. For example “Start to end”, “The process of constructing a car” etc
5. What are the advantages of ASP.NET MVC?
Following are some of the main benefits of ASP.NET MVC.
Separation of Code:
It makes it easier to manage complexity levels by dividing an application into the model, view, and controller.
Lightweight:
It doesn’t use view state and thus decreases the bandwidth of the requests.
Test-Driven Development:
It delivers better help for test-driven development (TDD).
Full features of ASP.NET:
One of the key benefits of using ASP.NET MVC is that it is built on top of the ASP.NET framework and hence most of the features of the ASP.NET like membership providers, roles, etc can always be utilized.
Testing is Isolation:
It provides the facility that different components can be tested in isolation.
Full control on generated HTML:
It has no server control instead a designer can design a page in pure HTML, Bootstrap, and CSS.
Less Complexity:
Because of the separation between all components, Huge applications become less complex.
Fast application development:
Multiple team members can work independently on different parts so the development becomes more fast and efficient.
6. Assembly name in which MVC is defined:
The MVC is usually defined in System.Web.Mvc.
7. List of different return type of a controller action method?
Basically, ActionResult is an abstract class and has different subtypes.
ViewResult: Renders a view as a web page.
PartialViewResult: Renders a partial view, which represents a section of a view that can be generated inside another view.
ContentResult: Returns a user-defined content type.
JsonResult: Returns a serialized JSON object.
RedirectToRouteResult: Redirects to another action method.
RedirectResult: Redirects to another action method by simply using its URL.
JavaScriptResult: Returns a executable script on the client-side.
FileResult: Returns binary outcome to write to the response.
EmptyResult: This means a return that is utilized if the action method must return a null/void result.
8. What are filters in ASP.NET MVC?
Filters are attributes which is used to perform some logic before and after an action method.
In ASP.NET MVC there are 5 types of filters. The order of execution of filter in ASP.NET MVC is the same.
- Authentication filter
- Authorization filter
- Action filter
- Result filter
- Exception filter
Note: We can use built-in filters and custom filters in MVC.
While developing an ASP.NET MVC application, you can use filters at the following levels:
Action method Level: When you use filters in an action method, the filter will execute only when the associated action method is accessed.
Controller Level: When you use filters in the controller, the Controller will execute for all the actions methods defined in the controller.
Application Level: When you use filters In an application, the filter will execute for all the actions methods and controllers present in the application.
9. What are action filters in ASP.NET MVC?
Action filters are elements that can be applied to a controller action method or on a controller. When applied to the controller, they are applicable for all actions in that controller. Action fitters allow us to add pre and post-processing logic to an action method. This means they let us change the way in which an action is executed.
Name a few commonly used action fillers?
- Authorize
- ChildActionOnly
- HandleError
- OutputCache
- RequireHttps
- Validatelnput
- VaIidateAntiForgeryToken
Can we create a custom action filter in ASP.NET MVC?
Yes, we can create a custom action filter in ASP.NET MVC.
10. What is routing in ASP.NET MVC?
The Routing in ASP.NET MVC application is a whole mechanism in which it will check the incoming Requests (i.e. URLs) and then map the request to the controller and their action method.
This mapping work by the routing rules which are defined for the application. We can perform this by adding the Routing Middleware to the request processing pipeline. So, the ASP.NET MVC Framework maps or connects the incoming Requests i.e. URLs to the Controllers action methods established on the routes configured in your application.
There are two different types of Routing in ASP.NET MVC:
Conventional Routing: We specify all the routes in the RouteConfig file. RouteConfig is available in the App_Start folder. All the routes should be registered to make them operational.
Attribute Routing: ASP.NET MVC supports a new type of routing called attribute routing. In Attribute-Based Routing, the route is decided based on the attributes which are configured either at the controller tier or at the action method tier.
11. What are important segments of routing in ASP.NET MVC?
There are three important segments of routing in ASP.NET MVC.
- ControllerName
- ActionMethodName
- Parameter
12. What is Route in ASP.NET MVC?
Route defines the URL pattern and handler information. All the configured routes of an application are stored in RouteTable and will be used by the Routing engine to determine the appropriate handler class or file for an incoming request. At its core, a route’s job is to map a request to action in ASP.Net MVC or .aspx file in ASP.Net WebForms.
13. What is RouteConfig file in ASP.NET MVC?
This file maintains the details of Routing for MVC. In each MVC application must have at least one route. This file defines the routing for MVC. we can also create custom routing.
14. What is the difference between TempData, ViewData, and ViewBag?
Similarities between ViewBag and ViewData:
- Data Passing techniques from the controller to View.
- ViewData and ViewBag are Data Dictionary objects.
- ViewData and ViewBag do not give compile-time errors.
- Both have short life means value becomes null when redirection occurs.
Difference between ViewBag and ViewData:
| ViewData | ViewBag |
| ViewData is accessible using string key values. | Dynamic type property. |
| Need typecasting. | Doesn’t require typecasting. |
TempData:
TempData is derived from TempDataDictionary class and it’s a dictionary object. It passes the data from current requests to subsequent requests.
Note: To pass data from the controller Controller It’s always good to use strongly typed snow models over ViewBag & ViewData. Strongly typed view modes provide compile-time error checking.
Conclusion:
The above-mentioned questions are listed after big software industry research and analysis. We have also contacted the technical recruiters of giant software houses to get you the most important ASP.NET Interview Questions. If you find some issue or want to discuss something please comment below or you can contact us.
