.NET Developer Interview Questions and Answers

.Net Interview Questions and Answers:

There is a list of the top frequently asked .NET Developer Interview Questions and Answers are given below.

1. What is Validation in ASP.NET?

Ans – In ASP.NET, Validation controls validate the user input data to ensure that useless, unauthenticated data don’t get stored.

2. Difference between ASP and ASP.NET.

Ans –

ASP	ASP.NET
1. It is a partially object oriented language.	1. It is fully object-oriented.
2. It uses language as VBScript, JScript.	2. It uses compiled language like C#, VB.Net, ASP.Net etc.
3. ASP is interpreted language.	3. ASP.Net is compiled language.
4. ASP uses ADO technology to connect database.	4. ASP.Net uses ADO.Net technology to connect the database.
5. ASP script code Written with in HTML code.	5. ASP.Net programming code written in C# language.

3. What is the Application Life Cycle in ASP.NET?

Ans – In ASP.NET, a WEB page has an execution life cycle that includes 8 phases:
1. Page Request: When a page requested by the user, ASP.NET parses and compiles that page.

2. Start: In this stage, page properties such as Request and Response are set. It also determines the Request type.

3. Initialization: During this stage, we can access the controls on the page but the control’s ViewState has not yet been initialized.

4. Load: In case of a postback, the control’s properties have been initialized from the ViewState.

5. Validation: Sometimes, there can be some validation set on the form.

6. Control Events: In the case of a postback, called the control events.

7. Rendering: During the rendering stage, the page calls the Render method for each control and thus each control generates the HTML output that is merged with the resulting HTML of the page.

8. Unload: In this stage, the generated page output has already been sent to the client and the page can be discarded.

4. What is the ViewState in ASP.NET?

Ans – Viewstate is a built-in structure for automatically retaining values amongst multiple requests for the same page. The ViewState is internally maintained as a hidden field on the page.

5. What is Postback in ASP.NET?

Ans – Postback is an event that triggered when an action performed by control on an asp.net page, when you click on a button the data on the page posted back to the server for processing.

6. What are built-in objects in ASP.NET?

Ans – The built-in objects in ASP.NET given below:
i. Application
ii. Request
iii. Response
iv. Server
v. Session
vi. Context
vii. Trace

7. How many types of configuration files are in ASP.NET?

Ans – There are three types of configuration files in ASP.NET:
i. Machine
ii. Application
iii. Security

8. What is HTTP Handler in ASP.NET?

Ans – It is a type that runs in response to a request made to an ASP.NET application. A request can be for any type of ASP.NET resource but it is the HTTP handler that generates the response. HTTP Handler used to map incoming requests to the appropriate IHttpHandler or IhttpHandlerFactory class.

9. Define Caching in ASP.NET.

Ans – Caching is the most important aspect of a high-performance web application. It provides a way of storing frequently accessed data and reusing the data.

10. How many types of session state modes are in ASP.NET?

Ans – There are four mode types of session state modes in ASP.NET.
i. In-process mode
ii. State Server mode
iii. SQL Server mode
iv. Custom mode

11. What is HttpModule in ASP.NET?

Ans – It enables you to configure the HTTP modules used within your application. This tag supports some subtags. The subtag specifies the HTTP module class to add to your application. It has two attributes, type and name.

12. Difference between ADO.NET and ASP.NET.

Ans –

ADO.NET	ASP.NET
1. It stands for ActiveX Data Objects.	1. It stands for Active Server Pages.
2. It is a Library.	2. It is a Framework.
3. It is a technology to access data from databases.	3. It is a technology through which dynamic web pages can be created.
4. Here, It provides to convert the data into XML format.	4. Here, We write our code into C#, VB.Net, ASP .Net etc.

13. Define DataSet and DataTable in .NET.

Ans – DataSet: Dataset provides a disconnected representation of result sets from the Data Source. It is completely independent of the Data Source. It provides much greater flexibility when dealing with related result sets.

DataTable: The DataTable class is located in the .NET Framework at System.Data.DataTable. It represents a table of in-memory data that is contained with a Dataset object. It can be created automatically by returning result sets from the DataAdapter to the Dataset object.

14. What is ASP.NET MVC?

Ans – ASP.NET MVC is an open-source framework built on top of Microsoft .NET Framework to develop the website and web application. ASP.NET MVC framework is the most customizable and extensible platform.

15. What is Routing in ASP.NET MVC?

Ans – Routing: Routing is characterized by a few attributes, such as name, URL pattern, default values, constraints, data tokens, and a route handler. The attributes you set most often are name, URL pattern, and default values.

16. What is Razor View Engine in MVC?

Ans – Razor View Engine: The Razor view engine employs a syntax that on one hand is familiar to nearly all ASP.NET developers. In ASP.NET MVC, the Razor view engine provides an alternate markup language to define the structure of view templates. According to Razor, a view template is an HTML page with a few placeholders and code snippets.

17. How many types of HTML Helpers?

Ans – An HTML Helper is a method that returns an HTML string. The string can represent any type of content that you want.
There are three types of HTML helpers:
1. Inline HTML Helpers
2. Built-In HTML Helpers
3. Custom HTML Helpers

18. Define Action methods in ASP.NET MVC.

Ans – Actions methods defined in the controller class and responsible for performing required operations on the user’s inputs like form values, query string values etc.

19. What are Data Annotations in ASP.NET MVC?

Ans – Data Annotation: Data annotations are attributes, and attributes don’t typically contain code. They just represent meta-information for other modules to consume. By using data annotations, you decorate your model objects with metadata. This isn’t expected to produce any visible effect: It all depends on how other components consume metadata.

20. How to enable and disable client-side validation in ASP.NET MVC?

Ans – We can enable the client-side validation.

We can disable the client-side validation.