1. Difference between ViewResult
and ActionResult
ViewResult
: It is a type ofActionResult
that specifically returns a view. It is used when an action method is designed to return a rendered HTML view to the client. TheViewResult
contains the model and view name that will be rendered.ActionResult
: This is the base class for all action results in ASP.NET MVC. It represents the result of an action method. AnActionResult
can return different types of responses, such as a view, JSON, a file, or a redirect.ViewResult
is derived fromActionResult
.
2. Importance of NonAction
Attribute
- The
NonAction
attribute is used to mark a method in a controller that should not be treated as an action method. This is useful when you want to create helper methods inside a controller that should not be callable as an action by clients.
3. Define MVC’s Partial View
- A partial view is a reusable view (i.e., a component) that is rendered within another view. It is used to encapsulate rendering logic for a portion of a page, such as a reusable widget or form. Partial views are stored in the
Shared
or relevant views folder and have the.cshtml
extension.
4. What is MVC Scaffolding?
- MVC Scaffolding is a code generation framework for ASP.NET MVC applications. It allows you to automatically generate code for CRUD (Create, Read, Update, Delete) operations, views, and controllers based on the model classes. This speeds up development by reducing boilerplate code.
5. Define ORM and its Use
- ORM (Object-Relational Mapping): It is a programming technique for converting data between incompatible type systems using object-oriented programming languages. ORMs allow developers to work with data in the form of objects rather than writing SQL queries. Examples include Entity Framework in .NET, Hibernate in Java, and Django ORM in Python.
6. Define POST and GET Action Types
GET: Used to request data from a specified resource. It retrieves data without changing it. GET requests are idempotent and safe.
POST: Used to submit data to a specified resource, often causing a change in the state or side effects on the server. POST requests are not idempotent.
7. If we place the log.txt
file in the ~/bin/ folder of an ASP.NET MVC application, will it affect the app?
- Placing a
log.txt
file in the~/bin
folder generally won’t affect the application directly, as the~/bin
folder is typically used for compiled assemblies. However, it’s not a good practice to place log files in this folder due to potential security and maintenance issues.
8. How to Implement Validation in MVC?
- Validation in MVC can be implemented using Data Annotations (e.g.,
[Required]
,[StringLength]
,[Range]
) on model properties. Additionally, client-side validation can be achieved by using jQuery validation and unobtrusive validation that work with Data Annotations.
9. Basic Folders in ASP.NET Core MVC Template Without Areas
- The basic folders are:
- Controllers: Contains controller classes.
- Views: Contains view files.
- Models: Contains model classes.
- wwwroot: For static files like CSS, JS, and images.
10. What is WebAPI?
- WebAPI is a framework that makes it easy to build HTTP services that reach a broad range of clients, including browsers and mobile devices. It is used to create RESTful services and can return data in various formats such as JSON or XML.
11. Benefit of Using IoC Container
- IoC (Inversion of Control) container helps in managing the dependencies of objects, promoting loose coupling, and enhancing testability by making it easier to inject mock or stub dependencies during testing.
12. Instances Where Routing is Not Required
- Routing is generally not required:
- When accessing static files (like CSS, JS, images) served directly from the server.
- In cases where a specific controller and action method are directly called using URL mapping that does not rely on routing.
13. Valuable Lifetime for an ORM Context in ASP.NET MVC
- The lifetime of an ORM context (like
DbContext
in Entity Framework) should be as short as possible, ideally scoped to a single HTTP request. It should be disposed of immediately after use to prevent memory leaks and ensure efficient resource usage.
14. Form Authentication in MVC
- Form authentication is implemented by setting up authentication in the
web.config
file and using the[Authorize]
attribute on controllers or actions. Users are redirected to a login page if they are not authenticated.
15. What is ViewState in MVC?
- In ASP.NET MVC, ViewState is not used. MVC architecture inherently avoids ViewState, favoring stateless behavior over state management used in traditional ASP.NET Web Forms.
16. Define Spring MVC
- Spring MVC is a module of the Spring Framework used to develop web applications following the Model-View-Controller design pattern. It offers a clean separation of concerns, flexible configuration, and the ability to use different view technologies.
17. Exception Handling in MVC
- Exception handling in MVC is commonly implemented using:
try-catch
blocks within action methods.- Custom error pages specified in the
web.config
. - Global error handling using the
Application_Error
event inGlobal.asax
or middleware in ASP.NET Core. - Exception filters like
HandleErrorAttribute
.
18. Define HTML Helpers
- HTML Helpers are methods that help generate HTML markup for views. They are used to streamline the creation of HTML elements in Razor views, e.g.,
@Html.TextBoxFor()
,@Html.DropDownListFor()
,@Html.BeginForm()
.
19. Database First Approach Using Entity Framework
- In the Database First approach, a model is generated based on an existing database. Entity Framework reads the database schema and creates model classes and a
DbContext
that match the database structure.
20. Need to Use Html.Partial
in MVC
Html.Partial
is used to render a partial view within a parent view. It provides a way to break complex views into smaller, reusable components.
21. How to Return JSON Response from an Action Method
- JSON response can be returned using the
Json
method in a controller action, like this:return Json(data);
wheredata
is the object to be serialized to JSON.
22. Benefit of Using Areas in MVC
- Areas allow you to organize large projects into smaller sections, each with its own set of controllers, views, and models. This is useful for modularizing applications and managing code more efficiently.
23. What is Model Binding?
- Model Binding is a feature of MVC that automatically maps data from HTTP requests (form data, query strings, etc.) to action method parameters. It simplifies the process of retrieving user input.