When you're ready to hire someone new for your team, it's important to think about what questions you should ask during the interview. You want to focus on the questions that are most relevant for your team and role you're hiring for, so you can understand how candidates will use their skills and experience to contribute to your company.

Look for someone with different areas of expertise from your own—this way, you can supercharge your team and get more done!

What Are the Questions Asked in an .NET / C# Interview?

Sitting someone down for an interview is often stressful and difficult, but with some preparation ahead of time you can make it much easier to find the right person for your team.

We’ve put together a list of .NET / C# interview questions that will help you evaluate candidates and determine whether they’re a good fit for your team.

Below are the .NET / C# interview questions we've had the most success with over the years. They're meant to be used as a guide. You can add your own questions and tweak them as needed.

We've divided them into four sections:

• C#

• ASP.NET Core

• Web API

• Architecture

C#

• What you understand by Value types and Reference types in .NET? Provide some comparison.

• What is Boxing and Unboxing?

• What is the difference between decimal, float and double in .NET?

• What is the purpose of the IDisposable interface?

• Does .NET support multiple inheritance?

• Explain how does Asynchronous tasks Async/Await work in .NET?

• Explain when to use Finalize vs Dispose?

• What is Managed and Unmanaged code?

• Explain Polymorphism?

• What is method overloading?

• What is scope of a Protected Internal member variable of a C# class?

• What are the differences between a class and structure?

• What is Garbage Collection?

• Explain Attributes in C#?

• What is Abstract Class in C#?

• Can I call a virtual method from a constructor/destructor?

• Does C# support a variable number of arguments?

• Is it possible to force garbage collector to run?

• Do structs support inheritance?

• What happens if you inherit multiple interfaces and they have conflicting method names?

• Could you explain the difference between Func vs. Action vs. Predicate?

• Explain the difference between Task and Thread in .NET

• Explain the difference between the Stack and the Heap.

• What is a delegate in .NET?

• Can you specify access modifiers in an interface?

• What are advantages of Garbage Collection?

• Web API

• What are HTTP Status codes? What are the most common status codes?

• What are the HTTP Methods?

• What is the concept of statelessness in REST?

• What is a REST Resource?

• How do you secure API endpoints?

• What are the core components of a HTTP Request?

• Explain how HTTP protocol works?

ASP.NET

• Explain the concept of middleware in ASP.NET Core?

• What is the MVC pattern?

• Explain the role of the various components of the MVC pattern?

• What is the purpose of the .csproj file?

• What is NuGet package manager?

• What is the purpose of the Program class?

• What is the purpose of the Startup class?

• What is model binding in ASP.NET?

• What is a cookie?

• What is routing, and how can you define routes in ASP.NET Core?

• Describe the Service Lifetimes.

• What is the Options Pattern in ASP.NET Core?

• How to use multiple environments in ASP.NET Core?

• How to prevent Cross-Site Scripting (XSS) in ASP.NET Core?

• How to enable Cross-Origin Requests (CORS) in ASP.NET Core?

• Explain the Filters.

Web API

• What are HTTP Status codes? What are the most common status codes?

• What are the HTTP Methods?

• What is the concept of statelessness in REST?

• What is a REST Resource?

• How do you secure API endpoints?

• What are the core components of a HTTP Request?

• Explain how HTTP protocol works?

Architecture

• How do you typically troubleshoot an issue?

• How would you improve performance in a slow endpoint?

• How can you improve scalability of your endpoints?

• What problems does Dependency Injection solve?

Interview Scorecard Templates by InterviewTime

To save everyone time, InterviewTime has created a list of templates available for you to use as-is or as inspiration for creating your own interview scorecard template based on what information will be useful for hiring in your company!

To learn more about scorecards, check out our article - Interview scorecard: pros & cons.