List of Frequently asked Interview Questions for C#.Net

1) What is .net framework?

2) What is abstract class?

3) What is Interface?

4) How does abstract class differ from Interface?

5) What is monitor object?

6) What will happen if any UI element is being updated by background thread in winform based multi-threaded application?

7) What are delegates?

8) Difference between DataReader and DataAdapter?

9) What is Garbage collector?

10) How does garbage collector work?

11) What is different between private and sealed class?

12) What is use of finally block?

13) How can you implement Singleton Design Pattern in C# code?


14) What is difference between read only variable and constants?

15) What is the use of static constructor? When will it be invoked?

16) Can we have parametrised static constructor?

17) Will finally block executed, if an exception is occurred?

18) What is RCW & CCW?

19) How will you cast Enum in integer and vice-versa?

20) Can a static class implement Interfaces?

21) Can multiple classes be inherited by derived class in C#?

22) What is unmanaged code in C#?

23) What are mutex and semaphors?

24) What are Factory design pattern and abstract factory design pattern?

25) difference between events and delegates.

26) How to notify MDI Form about change in any property of child form in winform based application?

27) What is threadpool?

28) What is GAC?

29) What is serialization?

30) What is windows service and how it differs from standard exe?

31) What is Strong Name of Assembly in C#?

32) Strong typing v/s weak typing?

33) What is CTS in dotnet?

34) What is CLS in dotnet?

35) What are the generics in .Net?

36) What are access modifiers in C#?

37) What is Boxing and Unboxing in C#?

38) How can we assign null value to Int?

39) What is use of Primary Interop Assembly?

40) Difference between value and reference type?