48 C# Interview Questions Any Interviewer Worth Their Salt Will Ask

With over 7,000 C#.Net programming jobs advertised every month that have an average salary of over $90,000, the demand for this type of developer has exploded. But why is the C#.Net labor market so hot right now? Well, more and more engineering departments are adopting C#.Net to build their software because it's similar to other common C-type languages like C++ and Java. This makes the language intuitive to learn -- in fact -- it's the fifth most popular programming language for building software.

To help you prepare for your next C#.Net developer interview and land the job, check out the following C#.Net interview questions most interviewers will ask you.

Take note that these questions mainly assess technical aptitude, but your interviewer will likely be looking for more than just the correct answer for every question -- they’ll want to see your critical thinking in action.

As Vitaly Futoriansky, a full stack developer lead at Sears Israel, explains, technical interviews reveal three attributes about a candidate: their depth of knowledge in C# programming language, their communication skills, and their ability to solve a problem. So after you take a look at these questions, consider crafting an answer to each one that will prove to interviewers that you posses the three attributes they're looking for. 

48 C#.Net Interview Questions

1. What is C#?

2. What are the advantages of using C#?

3. What are an object and class?

4. What is an Object Pool?

5. What is an abstraction?

6. What is polymorphism?

7. Is C# managed or unmanaged code?

8. How do you inherit a class in C#?

9. What’s the difference between Interface and Abstract Class?

10. What are sealed classes in C#?

11. What’s the difference between a struct and a class in C#?

12. What’s the point of using statement in C#?

13. How is Exception Handling applied in C#?

14. What are boxing and unboxing in C#?

15. What are the three types of comments in C#?

16. Can multiple catch blocks be executed in C#?

17. What’s the difference between static, public, and void? What’s the outcome of each one?

18. What are value types and reference types?

19. What’s the difference between ref and out parameters?

20. Can “this” be used within a static method?

21. What are Arrays in C#?

22. What is a jagged array in C#?

23. What’s the difference between Array and ArrayList?

24. What’s the difference between System.Array.CopyTo() and System.Array.Clone()?

25. What’s the difference between string and StringBuilder?

26. What are delegates in C#?

27. What’s a multicast delegate?

28. What is a Reflection in C#?

29. What is a Generic Class?

30. What are Get and Set Accessor properties?

31. What is Multithreading?

32. What is Serialization?

33. What are the different ways a method can be overloaded?

34. What is the accessibility modifier “protected internal”?

35. What are the different ways a method can be overloaded?

36. What is an object pool in .Net?

37. What are the most commonly used types of exceptions in .Net?

38. What are accessibility modifiers in C#?

39. What are nullable types in C#?

40. What’s the difference between is and as operators in C#?

41. What are Indexers?

42. What are Singleton Design Patterns?

43. Given an array of ints, write a C# method to total all the values that are even numbers.

44. Is it possible to store mixed data types like int, string, float, and char all in one array?

45. Describe dependency injection.

46. Write a C# program that accepts a distance in kilometers, converts it into meters, and then displays the result.

47. What’s the difference between the “constant” and “readonly” variables when using C#? When would you use each one?

48. Which preference of IDE do you have when using C#? Why?