✅ Introduction
Are you preparing for a job that involves Microsoft .NET or .NET Core? As a fresher stepping into the software development world, understanding the fundamentals and being ready to answer key .NET interview questions is essential.
.NET is a robust framework by Microsoft used to build scalable, secure, and high-performance applications. .NET Core, its cross-platform successor, has become the go-to choice for modern backend and cloud development.
In this blog from Capable Techies, we’ve handpicked 20 best .NET interview questions—spanning both .NET Framework and .NET Core—to help freshers ace technical rounds with confidence.
✅ Section 1: Basic .NET Interview Questions
1. What is .NET?
- A free, open-source developer platform to build apps for web, mobile, desktop, cloud, and more.
2. What is the difference between .NET Framework and .NET Core?
.NET Framework: Windows-only, older
.NET Core: Cross-platform, modern, lightweight
3. What are the key components of .NET?
CLR (Common Language Runtime)
FCL (Framework Class Library)
ASP.NET, ADO.NET, WinForms, WPF
4. What is the CLR in .NET?
- The Common Language Runtime manages memory, handles exceptions, and executes code.
5. What is a namespace?
- A container for classes and other types, used to organize code logically.
✅ Section 2: .NET Core-Specific Questions
6. What is .NET Core?
- A cross-platform version of .NET for building apps on Windows, Linux, and macOS.
7. Why is .NET Core faster than .NET Framework?
- It’s optimized for performance and lightweight deployments.
8. What are the advantages of using .NET Core?
Cross-platform
Performance and scalability
Microservices support
Docker-friendly
9. What is the difference between SDK and Runtime in .NET Core?
SDK: Contains compilers, tools
Runtime: Only needed to run apps
10. How does Dependency Injection work in .NET Core?
- Built-in DI allows for loosely coupled code and easier testing.
✅ Section 3: Intermediate-Level Questions
11. What are value types and reference types?
Value types (e.g.,
int,bool) store actual dataReference types (e.g.,
class,object) store references to data
12. What is the difference between var, dynamic, and object?
var: Compile-time typeddynamic: Runtime typedobject: Base type, needs casting
13. Explain boxing and unboxing.
Boxing: Converting value type to object
Unboxing: Converting object back to value type
14. What are extension methods in C#?
- Static methods that allow you to “add” methods to existing types.
15. What is middleware in ASP.NET Core?
- Software layers in the request pipeline that process HTTP requests and responses.
✅ Section 4: Real-World Coding Examples
16. Example: Print “Hello World” in ASP.NET Core
public class Startup {
public void Configure(IApplicationBuilder app) {
app.Run(async context => {
await context.Response.WriteAsync("Hello World!");
});
}
}
17. Example: Dependency Injection for a Service
services.AddTransient<IMyService, MyService>();
18. Example: Use Middleware for Logging
app.Use(async (context, next) => {
Console.WriteLine("Request handled");
await next();
});
19. Example: Model Validation in ASP.NET Core
[Required]
public string Name { get; set; }
20. Example: Create a simple API controller
[ApiController]
[Route("api/[controller]")]
public class ProductsController : ControllerBase {
[HttpGet]
public IActionResult GetAll() => Ok(new string[] { "Item1", "Item2" });
}
✅ FAQs – .NET & .NET Core Interview Questions
Q1. Is .NET Core still relevant in 2025?
- Yes. .NET 8 has unified .NET Framework, .NET Core, and Xamarin into one modern platform.
Q2. Should I learn .NET Framework or .NET Core?
- Start with .NET Core (.NET 6/7/8)—it’s the future and fully cross-platform.
Q3. What IDEs are best for .NET development?
- Visual Studio, Visual Studio Code, and Rider.
Q4. Is ASP.NET part of .NET or .NET Core?
- ASP.NET is part of both. ASP.NET Core is cross-platform and modular.
Q5. How important is Entity Framework in .NET interviews?
- Very important. It’s the default ORM used in enterprise .NET applications.
✅ Conclusion
The .NET ecosystem remains a powerful platform for building scalable applications. For freshers, knowing the difference between .NET Framework and .NET Core, understanding the core components, and being able to write simple APIs or web apps in ASP.NET Core can give a strong edge during interviews.
This guide, powered by Capable Techies, covered 20 best .NET interview questions for beginners, backed with examples and real-world relevance. Whether you’re preparing for your first tech interview or brushing up for a coding test, this list is your solid starting point.
📖 Read the full blog on Capable Techies to boost your .NET interview prep!
