| Aspect | ASP.NET WebForms | ASP.NET MVC |
|---|---|---|
| Model | Not explicitly defined, mixed with ASPX pages. | Clearly defined, separate from the view. |
| View | ASPX Pages | Razor or ASPX |
| Controller | Code-behind files linked to ASPX pages. | Separate controllers handle user input. |
| Routing | Based on physical file paths. | Based on controller actions. |
| State Management | ViewState for maintaining state. | Minimal use of state; relies on models. |
| HTML Control | Server controls that post back. | HTML helpers and partial views. A partial view in MVC is a specific type of Razor view that renders a portion of the HTML content in another view. It’s used to break down complex views into smaller, reusable components. Unlike regular views, partial views do not run on their own; they need to be called from other views or controllers. This helps in maintaining clean and DRY (Don’t Repeat Yourself) code by avoiding duplication. Partial views are ideal for reusable UI components like navigation menus, forms, or widgets across different views in an MVC application. |
| Unit Testing | Challenging due to tight coupling. | Easier due to separation of concerns. |
| Development Paradigm | Event-driven | Model-View-Controller (MVC) pattern. |
| Flexibility | Less, due to server controls and ViewState. | More, due to clean separation of concerns. |
| Performance | Can be slower due to ViewState and postbacks. | Generally better, no ViewState. |
| Learning Curve | Easier for beginners, especially with WinForms background. | Steeper, requires understanding MVC concepts. |
Interview Questions ASP MVC
| Question | Answer |
|---|---|
| What is the MVC pattern? | MVC stands for Model-View-Controller. It’s a design pattern that separates an application into three main logical components: the model (data), the view (UI), and the controller (business logic). This separation helps manage complexity, facilitates a clear structure for the app development, and enables individual development, testing, and maintenance of each component. |
| How does routing work in ASP.NET MVC? | In ASP.NET MVC, routing is managed by the RouteConfig class. Routes define URL patterns and how they map to specific controller actions. MVC uses this information to direct incoming requests to the correct controllers and actions, based on the URL and HTTP method. Routes are configured in the Global.asax file or in a dedicated route configuration file and are registered at application start. |
| Can you explain the lifecycle of an ASP.NET MVC request? | An ASP.NET MVC request goes through several steps: 1) URL Routing, where MVC matches the request to a route. 2) Controller Initialization, where the matching controller is instantiated. 3) Action Execution, where the action method on the controller is executed. 4) Result Execution, where the action result (view, file, etc.) is executed and rendered into an HTTP response. This lifecycle allows for modular handling of requests and responses within the framework. |
| What are Action Filters in ASP.NET MVC? | Action Filters are attributes that can be applied to controller actions or controllers themselves. They provide a way to run code before or after an action method executes, allowing for concerns such as logging, authentication, and caching to be handled separately from the action logic. There are different types of filters (Authorization, Action, Result, and Exception), each serving a specific purpose in the request handling pipeline. |
| How do you manage session state in ASP.NET MVC? | Session state in ASP.NET MVC can be managed using different strategies, such as using in-memory sessions, out-of-process servers (like SQL Server or Redis), or custom session providers. Sessions can store user data across requests for the duration of the user’s visit. ASP.NET MVC also supports cookie-based TempData for short-lived data and application cache for longer-lived data. Proper management ensures data persistence while minimizing the impact on scalability and performance. |
| Explain the difference between TempData, ViewData, and ViewBag. | - TempData is used to pass data from the current request to the next request, typically for redirection scenarios. It uses session state.- ViewData is a dictionary object for passing data from a controller to a view, and it requires typecasting for complex types.- ViewBag is a dynamic property that provides a more flexible way to pass data to the view. It does not require casting but has no compile-time type checking.All three are cleared after the request completes. |
| How can you implement security in ASP.NET MVC applications? | Security in ASP.NET MVC can be implemented using various features like authentication and authorization filters, SSL certificates for HTTPS, AntiForgery tokens to prevent CSRF attacks, and securing data with encryption. ASP.NET Identity can be used for managing users, passwords, and roles. Developers should also follow secure coding practices, such as validating input, sanitizing data, and implementing proper error handling to protect against SQL injection and other vulnerabilities. |
| What is Dependency Injection and how is it implemented in MVC? | Dependency Injection (DI) is a design pattern that allows a class’s dependencies to be injected at runtime rather than hard-coded. In ASP.NET MVC, DI can be implemented using various DI containers (e.g., Autofac, Unity, Ninject) to manage the instantiation and injection of dependencies. This facilitates loose coupling between classes, making them more modular, easier to test, and maintain. MVC supports DI natively in controllers, filters, and other components. |
| How do you handle errors in an ASP.NET MVC application? | Error handling in ASP.NET MVC can be implemented using custom error pages, try-catch blocks, and the [HandleError] attribute on controllers or actions. For global error handling, developers can use the Application_Error method in Global.asax. Logging frameworks (like log4net or NLog) can be integrated to log errors for monitoring and debugging. It’s also advisable to use custom error pages configured in the Web.config file to handle different error statuses in a user-friendly manner. |
| What is the role of the ViewModel in MVC? | A ViewModel is a model class that represents only the data we want to display on the view. It may aggregate data from multiple models or only a subset of a model.This separation allows for a cleaner, more organized way of passing data from the controller to the view. It can include display logic (not business logic) that helps in rendering the UI. This keeps the MVC model clean and focused on the business domain. |
| How do you optimize the performance of an ASP.NET MVC application? | Performance in ASP.NET MVC can be optimized through various techniques such as caching (output, data, application), async actions for non-blocking operations, bundling and minification of resources (CSS, JavaScript), using efficient data access strategies (e.g., Entity Framework performance tuning), optimizing images and static content delivery, and applying best practices for coding and design patterns. Monitoring tools can help identify bottlenecks for further optimization. |
| Describe how you would implement AJAX in an ASP.NET MVC application. | AJAX in ASP.NET MVC can be implemented using jQuery or vanilla JavaScript to make asynchronous requests to controller actions. These actions return partial views or JSON data, which can then be used to update the HTML content on the page without a full page refresh. This enhances the user experience by making the application feel more responsive and interactive. MVC also supports AJAX helpers that can simplify the implementation of AJAX-based functionality. |
Similarities with Blazor
| Similarity | Description |
|---|---|
| Development Model | Both Blazor and ASP.NET MVC leverage the Razor syntax for developing dynamic web pages. Razor provides a productive way to build dynamic web content with C#. |
| Component-Based Architecture | While Blazor operates on a more granular level with components, both frameworks encourage a modular approach to application development, promoting reuse and separation of concerns. |
| Use of C# and .NET Ecosystem | Blazor and ASP.NET MVC both allow developers to use C# and the extensive .NET library ecosystem, enabling the sharing of code and libraries across both server-side and client-side environments. |
| Visual Studio and Visual Studio Code Support | Developers can use Visual Studio and Visual Studio Code for both Blazor and ASP.NET MVC development, benefiting from features like IntelliSense, debugging, and integrated source control for a smooth development experience. |
| Dependency Injection | Both frameworks support Dependency Injection (DI) out of the box, allowing developers to write loosely coupled code, making it easier to manage, test, and maintain. |
| Routing | Blazor and ASP.NET MVC use a routing mechanism to navigate between views or components. They both allow the definition of route templates in the application, enabling URL-based navigation. |
| Authentication and Authorization | Blazor and ASP.NET MVC are integrated with ASP.NET Core’s security features, including built-in support for authentication and authorization, allowing developers to secure applications using standard or custom security mechanisms. |
| Support for Single Page Applications (SPA) | While Blazor is explicitly designed for building SPAs, ASP.NET MVC can also be used to create SPAs by leveraging client-side JavaScript frameworks alongside MVC’s server-side capabilities. This similarity extends to providing rich, client-side interactive experiences. |