Development teams use several software architectures to come up with applications. One is the MVC, fully known as the model view controller. This application design model is unique as it has three corresponding portions for developing applications with user interfaces.
You will need this article if you have a planned MVC-related interview, as we will look at some of the questions you should expect. Note that most of these questions are asked by some of the biggest tech companies, which gives you an upper hand. Take a look at the following:
1. MVC Is Made Up Of Three Portions. Mention Them
The model view controller consists of the model, view, and controller. The model collects the data to be used by the program, such as files, databases, or simple data-holding objects. At the same time, the view displays the projects or user interfaces in a given application, permitting communication between end-users. Lastly, the controller updates the other two portions and accepts user inputs.
2. Define The MVC Application Life Cycle
An MVC application’s life cycle is made up of two phases that mirror web applications whose main execution steps are understanding requests and sending the right responses based on them. The two phases in an MVC life cycle are creating a request object and sending the right response to the browser once the request has been understood.
3. Why Would You Advise A Developer To Use MVC?
4. Walk Us Through How To Execute An MVC Project
There are six main steps needed for the execution of MVC projects. The first request for the application is received, followed by routing, after which the request handlers are created. In the following steps, the controller is created and executed, the action is invoked, and the results are executed. This six-step technique is required to execute any MVC project.
5. Can You Mention The Main Functions In The Controller?
There are three main functions in the controller portion of MVC i.e before filter(), before render(), and after the filter. The after the filter() is generally used after every action is executed and rendering is done. It is usually the last controller method to run. On the other hand, the before filter() comes in handy in checking for active sessions or inspecting user permissions. As a general rule, it runs after every controller’s action. Lastly, the before render function, the least used, is needed for the manual calling of the render () before an auction ends.
6. Differentiate Between View And Partial View
There are four main differences between view and partial view. View normally has the layout page, which is not found in the partial view. The former also renders a view start page before rendering any view, while the latter operates without verifying a view star, making it impossible to put a common code within the view start.CSS HTML.page. Additionally, the view is not as lightweight as the counterpart and cannot permit the RenderPartial method, which is allowed in partial view. Lastly, the view has markup tags, including head and title, while the partial view lacks markup tags as it renders within the view.
7. Mention All The Features Of MVC
MVC has several features that explain its usefulness. It gives developers control over their HTML and URLs and supports TDD, commonly known as test-driven development. MVC also has URL routing for SEO-friendly URLs translating into highly advanced URL mapping for searchable and comprehensible URLs. Most people use MVC because of its high testability, extensibility, easy testability, and pluggable framework, forming some of its key features. This development architecture also uses existing features by ASP.NET, among many others, and has separated logic, i.e., controller, view, and model. Application tasks are also separated through input, business, and UI logic.
8. The MVC Architecture Has Always Been Compared To The 3-Tier Architecture. Can You Mention The Main Differences?
There are two main differences between the MVC and the 3-Tier Architecture, which lie in their usage and communication. As for the latter, the pattern does not directly communicate with the data layer, while all layers directly communicate in the MVC architecture, thanks to the triangle topology. Regarding usage, the former comes in handy in web applications where components operate on physically separate platforms, while the MVC architecture is used on applications running on single graphical workstations.
9. Take Us Through How MVC Works In Spring
For MVC to work in Spring, the DispatcherServlet must first receive a request communicated to HandlerMapping, which revokes the controller responsible for the request. The main controller processes the sent request by a service methods call, and the DispatcherServlet returns a ModelAndView object. The view name is then sent to a ViewResolver that finds the right view to invoke, after which results are rendered after the DispatcherServlet is passed to the view. The view renders and responds to the user through the model data.
10. What Normally Guides You When Creating MVC Applications?
There are several things to consider when creating an MVC Application. Whenever I am working on an MVC application, I remember that the development process is more complex than other web form-based applications and that once the application tasks have been separated, application maintainability automatically becomes higher. I also remind myself that ASP.net MVC cannot replace ASP.Net web forms-based applications and that the approach applied in the development has to be founded on the application requirements and features required to suit a given environment’s needs.
11. You Have Consistently Mentioned Web Forms And MVC. Can You Differentiate The Two?
There are several parameters that different web forms and MVC. First, MVC follows a pattern-based development model while ASP.Net uses an event-driven development model. The former also uses web forms syntax, while the latter follows the customizable syntax. Additionally, net web forms allow state-for-state management at the client-side, while MVC lacks view state support. Other differences include: Web Forms allow code reusability thanks to user controls while MVC comes with partial views to serve the same function, Web Forms perform automatic controls’ state management while MVC does manual state management, and the former offers less control over rendered HTML while the latter grants full control.
12. Define MVC In Angularjs
It is common knowledge that Angular.js follows the MVC architecture. Of the three portions, the controller represents the layer with the business logic. It has stored functions triggered by user events, which are its parts. In this case, the views symbolize the presentation layer for end-users while models are data representatives; such data does not usually have to be complicated and can be as simple as containing primitive declarations.
13. Define The Working Mechanism MVC In Angularjs
In AngularJS, the controller mainly controls the data passed to the view, meaning that the scope and view have two-way communication. Functions can be called on the scope using the view properties while view events call methods. In this arrangement, the scope exposes a model to the view, where the former can be modified through defined scope methods triggered by view events. On the other hand, the directives manipulate the DOM. A good practice would be to have controllers that are based on functionality. The working mechanism of MVC in AngularJS is therefore not as complicated.
14. Mention Some Of The Reasons Why We Need The PHP MVC Framework
One of the reasons developers are often asked to use the PHP MVC Framework is because it makes working with complex technologies easier. This is normally achieved through adhering to professional coding standards, making all complex implementation details invisible, offering standard methods used to build applications, and lastly, improving a developer’s productivity because these frameworks partially implement base implementations, which covers activities such as sanitizing user inputs and connecting to a given database.
15. Can You Mention Some Of The Most Common PHP MVC Frameworks?
There are four main PHP MVC Frameworks that I have used in my career. I love Zend, a powerful framework that supports Web 2.0 and web services creation. It is also secure, reliable, scalable, fast, and has APIs from major vendors such as Yahoo and Google. Others include Kohana, a secure hierarchical MVC and lightweight framework with rich components for rapid applications development; CakePHP, a model built on Ruby and Rails and known for convention over configuration, software design patterns, and ActiveRecord, among many other concepts.
16. Explain The Roles Of The Different MVC Components?
The three main MVC Components are presentation, control, and abstraction. The main role of the abstraction component is to ensure that the business domain found in the application is functional, while the presentation component comes in handy as it aids in the visual representation of different abstractions found in the application. Lastly, the control component ensures consistency within the abstraction present within the system and the presentation seen by the user. It also allows a given system to communicate with other controls. Each component, therefore, plays its own role even though they may interdepend on each other.
17. Mention The Different Logical Layers In The MVC Pattern
There are three logical layers in the MVC Pattern responsible for different useful MVC functions time controller logic, which acts as input control, model logic which is the business layer, and the view logic, which is the official display layer. The controller logic is usually part of the application charged with user interaction, while the model logic is charged with handling the logic for the data application. The latter retrieves data before storing them in the database. The view logic is charged with the data display. It has views obtained from the model data even though they can be created using other methods.
18. What Do You Know About The Razor View Engine?
Contrary to many people’s beliefs, the razor view engine is an HTML markup language written on the server-side using the C# language. Given that Razor does not have a link with Asp.net MVC, it uses a view engine that relies on the Razor View to produce an HTML output. The razor view engine, therefore, uses a semicolon to end a statement and relies on .cshtml as its file extension. It is also worth mentioning that there are two main block statements on Razor, i.e., single statement block and inline expression and multiple statement block with inline expression.
19. Can You Mention The Limitations Of MVC?
Despite its usefulness and applicability, MVC comes with several limitations worth exploring. Every developer knows that the model view controller architecture has a complex model pattern compared to its counterparts, such as web forms. Even though it allows different types of development, it calls for several programmers for multiple development purposes. This application development architecture also requires knowledge of different technologies and doesn’t adequately work for small applications. Lastly, view, which is one of the MVC model’s main components, has inefficient data access.
20. Can You Explain What Routing Is In MVC And Its Different Segments
Routing is a pattern-matching scheme in MVC that maps incoming browser data requests to concrete and well-defined controller actions. It has three essential parts segments: parameter, ActionMethodName, and ControllerName. The methods to be executed for URLs are often controlled by the MVC routes, which have several properties. First, the URL pattern used for the handler is usually the route name. The default parameter value only gets assigned when the parameter is created and all the literal values and variable placeholders a contained in the URL pattern.
21. Can You Mention The Features Of The New MVC Version?
The ASP.NET MVC2, released in March 2010, comes with several new features that have greatly benefitted developers. It offers support for page section rendering and partitioning of large applications, has a strongly-typed HTML helper, and improved visual video tooling provides attribute-based model validation on both the client and the server and offers asynchronous controller support. Other features include several helper functions and utilities, UI helpers with automatic scaffolding and customizable templates, and API enhancements and pro features from different developers.
22. Where Does Separation Of Concerns Happen In MVC?
The separation of concerns usually happens between the model charged with data processing and the other application parts. The ownership of the views and controllers can sufficiently explain the concept of separation. Views are presentation forms of applications and are not guaranteed knowledge of the requests coming from the controller. The controller is an independent component tasked with handling requests and passing them on in accordance with the defined routes and rendering views. These business entities, i.e., view, controller, and model, exist in physical layers independent of one another.
23. Explain What Display Modes Are In MVC4
MVC4 is one of the latest versions of this application development platform. It has display modes that permit the selection of different views depending on the requesting browser through a convention-based approach. MVC4 has a default view engine that first searches views whose names end with Mobile. CSS HTML when the agent points to a known device. It is possible to register one’s custom device modes that use personal custom criteria- a one-code statement that contains everything. There are specific codes that should be used when creating custom device modes.
24. Explain JSON Binding, Dependency Resolution, And Bundle. Config In MVC
The development of the JsonValueProviderFactory created room for JSON binding, giving action methods the green light to model-bind data in JSON format after acceptance. Jason binding comes in handy in Ajax scenarios such as special data mining and client templates.
Dependency Resolution was introduced in MVC3 to simplify the application of dependency injection in applications, making it easier to decouple application components and improve their testing and configuration.
Lastly, Bundle. Config plays an important role in MVC as it registers modification system bundling. Some bundles added by default include jQuery libraries such as default CSS references and Modernizer.
25. Explain The Different Helpers In MVC
There are two main helpers in MVC, namely HTML and AJAX helpers. HTML helpers have a similar working mechanism as the controls used in traditional web forms, just that they are more lightweight and lack both events and view states. They return the HTML string with the possibility of direct rendering to the HTML page. You only need to override the HtmlHelper class to create custom HTML helpers.
The other type in MVC is the AJAX helpers used to build AJAX-enabled elements such as enabled forms and links for asynchronous request performance. Examples of AJAXHelper class found in the namespace include the system. web.MVC
These are some of the questions you should expect in your upcoming MVC interview. Please take note of their technical nature, which should tell you that you need to focus more on the technical aspects of MVC. We wish you all the best in your scheduled interview.