ASP.NET is a powerful open-source web framework developed by Microsoft in 2002. It was designed by Anders Hejlsberg to help developers build websites, web apps, and online services more easily. Over time, it has become a popular choice for creating fast and secure web applications, especially in large companies. If you are applying for a job that involves web development, you will likely be asked questions about ASP.NET. To help you get ready, we have listed the 25+ most common ASP.NET interview questions along with simple answers you can understand and remember.
Fun Fact – According to W3Techs, ASP.NET is used by 5.2% of all websites.
Note – We have divided the ASP.NET interview questions into basic-level, for freshers, for experienced professionals, and advanced-level, to help you prepare better.
Basic Level ASP.NET Interview Questions
Here are the basic ASP DOT NET interview questions and answers to build a strong foundation before moving to advanced topics.
- What is ASP.NET and how does it work?
ASP.NET is a web development framework by Microsoft. It runs on the .NET platform and helps build dynamic websites, apps, and services. It uses a request-response model where user actions are sent to the server, processed, and the server returns an HTML response.
- How does the page life cycle work in ASP.NET?
The page life cycle includes several stages: Page Request, Start, Initialization, Load, Postback Event Handling, Rendering, and Unload. Each stage allows developers to interact with the page differently. For example, controls are initialized during the Init stage, and event handling happens after Load.
- What is ViewState and how is it used?
ViewState stores data across postbacks in ASP.NET Web Forms. It keeps the state of controls like textboxes and dropdowns without needing server-side storage. ViewState data is encoded and sent to the client inside a hidden field.
- Explain the role of Global.asax in an ASP.NET application.
Global.asax (also called the application file) handles application-level events like Application_Start, Session_Start, and Application_Error. It’s useful for logging, initializing settings, or managing global variables during the app’s lifecycle.
- What is the difference between Server.Transfer and Response.Redirect?
Server.Transfer transfers control to another page on the server without changing the URL. It’s faster and stays on the same server. Response.Redirect tells the browser to request a new page, changing the URL and causing a full round-trip to the client.
ASP.NET Fresher Interview Questions
These are the most commonly asked ASP.NET fresher interview questions and answers to help beginners get interview-ready.
- What is the difference between ASP.NET and ASP.NET Core?
ASP.NET is the older framework that runs on Windows and supports Web Forms, MVC, and Web API. ASP.NET Core is cross-platform, faster, open-source, and uses a unified MVC/Web API model. It also supports modern features like minimal APIs and better dependency injection.
- What are the main components of ASP.NET architecture?
Key components include:
- HTTP Runtime: Handles requests.
- HTTP Modules and Handlers: Control how requests are processed.
- Page Handler: Executes .aspx pages.
- Server Controls: Help in UI rendering.
- Configuration Files: Control behavior at runtime.
- How do you handle errors in ASP.NET?
You can use try-catch blocks for local error handling. For global errors, use Application_Error in Global.asax. The customErrors tag in web.config can also redirect users to friendly error pages.
- What is the use of the web.config file?
It stores configuration settings like connection strings, error pages, session state, and security rules. The file is in XML format and affects how the ASP.NET app runs.
- What are user controls and custom controls in ASP.NET?
User controls are .ascx files reused across pages. They’re easy to create and maintain. Custom controls are compiled into DLLs and used across multiple projects. They offer more flexibility but require more effort to build.
ASP.NET Interview Questions for Experienced Professionals
Let’s cover some advanced ASP.NET interview questions and answers that experienced professionals are likely to face during technical interviews.
- How do you manage session state in a load-balanced environment?
In load-balanced setups, use out-of-process session state. Options include SQL Server or a distributed cache like Redis. This keeps session data consistent across all servers in the farm.
- What is dependency injection in ASP.NET Core?
Dependency Injection (DI) is built into ASP.NET Core. It helps manage object creation and lifetime. You register services in Startup.cs using ConfigureServices, and the framework injects them where needed.
- Explain middleware in ASP.NET Core.
Middleware are components that handle requests and responses in a pipeline. They can log requests, check auth tokens, serve static files, or return responses. Order matters — they’re executed in the sequence they’re added in Startup.cs.
- What is the difference between synchronous and asynchronous controllers?
Synchronous controllers block threads while waiting. This can limit scalability. Asynchronous controllers use async and await, freeing up threads for other requests. Async is better for I/O-bound operations like API calls or database access.
- How do you implement security in an ASP.NET application?
Use authentication (e.g., cookie-based, JWT) and role-based or policy-based authorization. Validate all user inputs to avoid injection attacks. Use HTTPS, security headers, and secure cookie settings to protect data during transmission. Also, keep frameworks and libraries up to date.
2 Years Experience Interview Questions in ASP.NET
- What is the difference between a Master Page and a Layout in ASP.NET?
- Can you describe a project where you used ASP.NET extensively?
- How do you approach debugging in large ASP.NET applications?
- You are seeing performance issues in an ASP.NET app. How would you troubleshoot it?
ASP.NET 3 Years Experience Interview Questions
- How do you handle session management across multiple servers?
- Can you share your experience working with .NET and databases?
- How do you deal with sudden production bugs?
- Your team reports a memory leak in a web app. How would you respond?
ASP.NET Interview Questions for 5 Years Experienced
- What’s the difference between IHttpModule and IHttpHandler?
- How have you led a team or module in ASP.NET projects?
- Describe a time you had to resolve a difficult coding issue.
- A client requests zero downtime during deployment. What’s your approach?
ASP.NET Core Interview Questions for 8 Years Experienced
- How is dependency injection handled in ASP.NET Core?
- How do you keep up with changes in .NET Core and apply them at work?
- Describe a time you dealt with conflicting opinions on code architecture.
- You are asked to migrate a legacy ASP.NET app to .NET Core. What’s your plan?
ASP.NET Interview Questions for 10 Years Experienced
- What are your go-to design patterns in ASP.NET applications?
- What’s been your biggest challenge in 10 years of ASP.NET work?
- How do you mentor junior developers on ASP.NET concepts?
- You are asked to build a multi-tenant SaaS platform in ASP.NET. How do you approach it?
Advanced Level ASP.NET Interview Questions
Here is a list of challenging ASP.NET interview questions answers to test your deep understanding of concepts, architecture, and real scenarios.
- How would you implement custom middleware in ASP.NET Core?
Create a class with an Invoke or InvokeAsync method that takes HttpContext. Write logic inside this method. Register the middleware in Startup.cs using app.UseMiddleware<YourMiddleware>(). It’s useful for logging, custom headers, or request filtering.
- What is the role of the IApplicationBuilder interface?
IApplicationBuilder builds the request pipeline. It’s used in the Configure method of Startup.cs. It lets you add middleware like routing, authentication, or custom logic. Each middleware decides whether to pass the request to the next.
- How do you handle configuration and secrets in ASP.NET Core apps?
Use appsettings.json for general configuration. For secrets, use environment variables or the Secret Manager tool in development. In production, use Azure Key Vault or similar secure storage. Load these using the built-in Configuration API.
- Explain how to use SignalR in ASP.NET.
SignalR enables real-time communication between server and clients. Add the SignalR NuGet package, configure it in Startup.cs, and create a Hub class. Clients connect using JavaScript or C# and can receive live updates from the server.
- What is the purpose of the ConfigureServices method in Startup.cs?
This method registers services used by the app, like DbContext, Identity, or custom services. It sets up dependency injection. It runs before the app starts handling requests.
ASP.NET Core Interview Questions
Here are commonly asked ASP.NET Core interview questions and answers for experienced professionals.
- What are the key differences between ASP.NET MVC and ASP.NET Core MVC?
ASP.NET Core MVC is part of a cross-platform framework. It is modular, faster, and combines MVC and Web API. ASP.NET MVC runs only on Windows and is more tightly coupled with System.Web.
- How does routing work in ASP.NET Core?
Routing maps URLs to controllers and actions. You configure it using app.UseRouting() and app.UseEndpoints() in Startup.cs. It supports both conventional and attribute routing. Attribute routing gives more control over URL patterns.
- What is Kestrel in ASP.NET Core?
Kestrel is a lightweight, high-performance web server built for ASP.NET Core. It can run standalone or behind a reverse proxy like IIS or Nginx. It’s cross-platform and works well with cloud deployments.
- How do you configure middleware in the Startup class?
Middleware is added in the Configure method using IApplicationBuilder. Use methods like app.UseRouting(), app.UseAuthentication(), and custom middleware. The order matters – incorrect placement can break the pipeline.
- What are tag helpers in ASP.NET Core?
Tag helpers are server-side components that run on Razor views. They make HTML elements dynamic. For example, <form asp-controller=”Home” asp-action=”Submit”> generates a proper form action. They replace some older HTML helpers for cleaner syntax.
Note – These ASP.NET Core interview questions and answers will help you prepare for modern, high-performance web application roles.
Also Read - Top 30+ MVC Interview Questions and Answers
Other Important ASP.NET Interview Questions
Here are some other important ASP DOT NET interview questions that are frequently asked across various roles and experience levels.
ASP.NET Web API Interview Questions
- What is ASP.NET Web API and how is it different from MVC?
- How do you secure an ASP.NET Web API?
- What are filters in Web API?
- How do you implement versioning in Web API?
ASP.NET and C# Interview Questions
- How does ASP.NET use C# in the code-behind model?
- What is the role of delegates and events in ASP.NET apps?
- How can LINQ be used in ASP.NET applications?
- What is the difference between ref and out parameters in C#?
ASP.NET Interview Questions C# Corner
- What is the App Domain Concept in ASP.NET?
- What are the Advantages of ASP.NET?
- What is Ajax in ASP.NET?
- What is the use of CheckBox in .NET?
ASP.NET Web Forms Interview Questions
- What is the difference between Web Forms and MVC?
- How do you maintain state in ASP.NET Web Forms?
- What are the different types of validation controls in Web Forms?
- Explain the concept of postback in Web Forms.
Tips to Prepare for ASP.NET Interview
Here are some helpful tips you can follow to prepare for ASP.NET interview.
- Know the lifecycle of a page and the difference between Web Forms and MVC/Core.
- Practice coding simple projects using ASP.NET Core to understand routing, controllers, and views.
- Prepare for practical questions, like debugging or improving app performance.
- Build or review real projects to explain in interviews – they prefer experience over theory.
- Review commonly asked ASP.NET interview questions.
- Use GitHub to explore open-source ASP.NET projects and understand code structure.
- Review recent updates in ASP.NET Core for 2023–2025.
- Mock interviews help – practice answering out loud.
Wrapping Up
So, these are the 25+ ASP.NET interview questions that are commonly asked by top companies in India. From basics to advanced topics, each question helps you understand what interviewers expect.
And hey, if you want to make your job search easier, visit Hirist. This online job portal is designed for IT professionals. Here, you can easily find the best ASP.NET jobs in India, all in one place.
FAQs
What are the common Accenture ASP.NET interview questions?
Here are some commonly asked ASP.NET interview questions at Accenture.
- How do you handle cross-site scripting (XSS) in ASP.NET?
- Explain caching strategies used in ASP.NET applications.
- What is role-based authentication in ASP.NET?
- How do you test and deploy ASP.NET applications?
Are Infosys ASP.NET interview questions tough?
They are not too tough if you have worked with ASP.NET regularly. Infosys usually asks questions about real-life scenarios, error handling, and design approaches. Common questions include,
- What is the difference between authentication and authorization?
- How do you consume REST APIs in ASP.NET?
- What tools do you use for ASP.NET development?
- Explain the difference between Razor and Web Forms syntax.
Also Read - Top 50+ REST API Interview Questions and Answers
How to answer NET ASP interview questions?
Understand core concepts like lifecycle, routing, and state management. Use real examples, keep answers short, and explain things clearly in your own words.
What is the average salary of an ASP.NET developer in India?
According to AmbitionBox, the ASP.NET Developer salary in India ranges from ₹1.2 Lakh to ₹7.7 Lakhs for professionals with less than 1 year to 5 years of experience.
Which companies hire ASP.NET developers in India?
Top companies include Infosys, TCS, Accenture, Wipro, HCL, Tech Mahindra, and Capgemini. Many startups and mid-sized firms also hire actively for ASP.NET roles.
Do I need to learn ASP.NET Core as well?
Yes, most companies now prefer ASP.NET Core because it’s faster, cross-platform, and more flexible. It’s a good idea to learn both.
