C# .NET Interview Questions

 Questions on Stack, Heap, Boxing, Unboxing, Array, ArrayList, Generics, Threading.

 Question 1 :- Explain difference between .NET and C# ? 5:00

 Question 2 :- .NET Framework vs .NET Core vs .NET 5.0 3:17

 Question 3 :- What is IL ( Intermediate Language) Code ?

 Question 4 :- What is the use of JIT ( Just in time compiler) ?

 Question 5 :- Is it possible to view IL code ?

 Question 6 :- What is the benefit of compiling in to IL code ?

 Question 7 :- Does .NET support multiple programming languages ?

 Question 8 :- What is CLR ( Common Language Runtime) ?

 Question 9 :- What is managed and unmanaged code ?

 Question 10 :- Explain the importance of Garbage collector ?

 Question 11 :- Can garbage collector claim unmanaged objects ?

 Question 12 :- What is the importance of CTS ?

 Question 13 :- Explain CLS ?

 Question 14 :- Difference between Stack vs Heap ?

 Question 15 :- What are Value types & Reference types?

 Question 16 :- Explain boxing and unboxing ?

 Question 17 :- What is consequence of boxing and unboxing ?

 Question 18 :- Explain casting, implicit casting and explicit casting ?

 Question 19 :- What can happen during explicit casting ?

 Question 20 :- Differentiate between Array and ArrayList ?

 Question 21 :- Whose performance is better array or arraylist ?

 Question 22 :- What are generic collections ?

 Question 23 :- What are threads (Multithreading)?

 Question 24 :- How are threads different from TPL ?

 Question 25 :- How do we handle exceptions in C#(try/catch)?

 Question 26 :- What is the need of finally?

 Question 27 :- Why do we need the out keyword ?

 Question 28 :- What is the need of Delegates ?

 Question 29 :- What are events ?

 Question 30 :- Whats the difference between Abstract class and interface ?

 

 Questions on Delegates, Event & Delegates vs Events.

 Question 31 - What is a Delegate and how to create a Delegate?

 Question 32 - Where have you used Delegates?

 Question 33 - What is a Multicast Delegates?

 Question 34 - What is an Event?

 Question 35 - How to Create an Event?

 Question 36 - Delegate VS Events.

 Question 37 :- Why do we need OOP ?

 Question 38 :- What are the important pillars of OOPs ?

 Question 39 :- What is a class and object ?

 Question 40 :- Abstraction vs Encapsulation?

 Question 41 :- Explain Inheritance ?

 Question 42 :- Explain virtual keyword ?

 Question 43 :- What is overriding ?

 Question 44 :- Explain overloading ?

 Question 45 :- Overloading vs Overriding ?

 

 Questions Polymorphism, Static vs Dynamic polymorphism and operator overloading.

 Question 46 :- Explain static vs dynamic polymorphism ?

 Question 47 :- Explain operator overloading ?

 

 - Tricky Questions around Abstract classes and Interfaces.

 Question 48 :- Why do we need Abstract classes ?

 Question 49 :- Are Abstract methods virtual ?

 Question 50 :- Can we create a instance of Abstract classes ?

 Question 51 :- Is it compulsory to implement Abstract methods ?

 Question 52 :- Why simple base class replace Abstract class ?

 Question 53 :- Explain interfaces and why do we need it ?

 Question 54 :- Can we write logic in interface ?

 Question 55 :- Can we define methods as private in interface ?

 Question 56 :- If i want to change interface whats the best practice ?

 Question 57 :- Explain Multiple inheritance in Interface ?

 Question 58 :- Explain Interface Segregation principle ?

 Question 59 :- Can we create instance of interface ?

 Question 60 :- Can we do Multiple inheritance with Abstract classes ?

 

 Answering the most asked Question "Abstract classes vs Interface".

 Abstract Class vs interface interview questions and answers.

 Question 61 :- Abstract Class vs interface interview questions and answers.

 Question 62 :- Why do we need constructors ?

 Question 63 :- In parent child which constructor fires first ?

 Question 64 :- How are initializers executed ?

 Question 65 :- How are static constructors executed in Parent child ?

 Question 66 :- When does static constructor fires ?

 

 Questions around Shadowing, Sealed, Nested classes and partial classes.

 Question 70 :- What is Shadowing?

 Question 71 :- Explain method hiding?

 Question 72 :- Shadowing vs Overriding ?

 Question 73 :- When do we need Shadowing ?

 Question 74 :- Explain Sealed Classes ?

 Question 75 :- Can we create instance of sealed classes ?

 Question 76 :- What are nested classes and when to use them ?

 Question 77 :- Can Nested class access outer class variables ?

 Question 78 :- Can we have public,protected access modifiers in nested class ?

 Question 79 :- Explain Partial classes ?

 Question 80 :- In What scenarios do we use partial classes ?

 

 Question 81 :- What is SOLID ?

 Question 82 :- What is the full form of SOLID ?

 Question 83 :- What is the goal of SOLID ?

 Question 84 :- Explain SRP with A example ?

 Question 85 :- What is the benefit of SRP ?

 Question 86 :- Explain OCP with a example ?

 Question 87 :- What is the benefit of OCP ?

 Question 88 :- Can you explain LISKOV Principle and it's violation?

 Question 89 :- How can we fix LISKOV Problem ?

 Question 90 :- Explain Interface Segregation Principle ?

 Question 91 :- Is there a connection between LISKOV and ISP ?

 Question 92 :- Define dependency inversion ?

 Question 93 :- What is higher level module and lower level module ?

 Question 94 :- How does dependency inversion benefit, show with an example ?

 Question 95 :- Will only Dependency inversion solve decoupling problem ?

 Question 96 :- Why do developers move object creation outside high lever module ?

 Question 97 :- Explain IOC ( Inversion of Control) ?

 Question 98 :- Explain Dependency Injection with an example ?

 Question 99 :- Is SOLID, IOC and DI design pattern or Principle?

 Question 100 :- Is only SOLID Enough for good code/ architecture ?