20+ Technical .NET Developer Interview Questions

.NET developers design customized software solutions tailored to individual business needs using Microsoft’s .NET platform. These programming specialists help businesses build powerful, efficient software to handle daily functions.

When interviewing a .NET developer, you need to look for the skills that align with the role’s responsibilities. Keep reading to learn more about .NET developers, plus the best .NET developer interview questions to ask.

What Skills Should a .NET Developer Have?

.NET developers work closely with multiple departments to write code for adaptable software solutions. They also provide technical support for team members experiencing issues with the software. On a given day, a .NET developer may have to do any of the following:

Develop, test, and maintain .NET software applications
Collaborate with other departments to identify, design, and execute new features
Troubleshoot, debug, and optimize code
Stay up to date with the newest technologies and best practices in .NET development
Provide support for company software issues
Communicate with team members on how to operate new software

.NET developers are responsible for creating new software as well as working with end users to ensure the software works properly. As a result, they need to be skilled in multiple .NET programming languages and comfortable working closely with people in multiple departments.

Skills a qualified .NET developer should have include:

Programming languages: .NET developers may need to work with multiple programming languages in the .NET framework, like C#, F#, and VB.NET. They should be comfortable writing lines of code and optimizing them to run more efficiently.
Web development: In addition to software applications, .NET developers often create web applications. They should be able to use ASP.NET, HTML, and JavaScript.
Database management and Object Relational Mapping (ORM): .NET developers work with massive amounts of data. They should be comfortable working with data languages like SQL and ADO.NET.
Software architecture: Because .NET developers create systems for use by multiple departments, they need to be able to design software solutions that are easy to use. Knowledge of SOLID principles and design patterns will help in this regard.
Verbal communication: Many of the people .NET developers work with won’t come from backgrounds in technology. They need the ability to communicate advanced technological ideas in simple terms.

Top .NET Developer Interview Questions

Before asking specific .NET developer interview questions, start with some general IT questions. Then you can move to these questions.

Basic .NET Concepts

What is the .NET Framework, and how does it work?
Explain the role of the Common Language Runtime (CLR) in .NET.
What is the difference between value types and reference types in .NET?
How does the Global Assembly Cache (GAC) handle versioning?
What is the purpose of the Globalization and Localization features in .NET?

Programming Language Proficiencies

What are some of the differences between abstract classes and interfaces in C#?
What is the purpose of the “using” statement in C#?
Describe the concepts of inheritance, polymorphism, and encapsulation in C#.
How does exception handling work in C#?

ASP.NET and Web Development

What is the role of ASP.NET in .NET applications?
Explain the MVC pattern and its role in ASP.NET.
What is the difference between ASP.NET Web Forms and ASP.NET MVC?
Describe how to use session state and application state in ASP.NET.
How does ASP.NET deal with authentication and authorization?

Database and Entity Framework

Explain the differences between ADO.NET and Entity Framework.
Describe some of the relationship types in Entity Framework.
How would you optimize database queries in a .NET application?

Advanced Topics and Best Practices

Discuss the principles of SOLID and their application in .NET development.
How can you improve the performance of a .NET application?
Explain asynchronous programming in C# and its benefits.
What are dependency injection and inversion of control, and how are they implemented in .NET?

Hire a .NET Developer with Insight Global

Finding a qualified .NET developer means gauging candidates’ technical skills and experience. Strong .NET developer interview questions will help you identify the right candidate to hire.

For companies looking to source talent from a wide pool, Insight Global’s staffing services can help. Our team of recruiters will find the right candidate for your team, and you won’t pay until the new hire starts. Contact us today to learn more about our staffing services.