This post is for programmers gearing for their first C# OOPs interview. C# is the most popular object-oriented programming language used by millions of developers. So every interviewer rates your C# programming skills based on how well-versed you are in OOPs concepts.
Hence, we picked 25 key OOPs questions for C# programmers. It is a quick way to brush up programming skills and knowledge of C# OOPs concepts. We’ve clubbed both the theoretical and coding questions together so that you can focus on coding as well as theory.
If you also like to explore additional C# topics for interview prep, then do visit the C# interview section to check hundreds of programming questions and answers.
However, before you proceed, please have a look at the below questions/areas that you must also prepare for securing a C# programming job.
1. What are types in C# – Value & Reference types?2. What are access modifiers in C#?3. What are the basic OOPs concepts in C#? a. class (Abstract, partial, sealed, static, etc.) b. enum c. struct d. interface4. What do you know about Partial types and Partial methods?5. What is the use of ‘typeof’ keyword in C#?6. How do you call the multiple constructors of a class with single object creation?7. How to debug a running C# program?8. How do you implement an interface and call its methods?9. What is the use of “REF” & “OUT” keyword in C#?10. How will you use “params” & “dynamic” in method parameters?
Now, it’s time that you put your C# programming skills to test as the 25 C# questions are waiting for you next.
3Is it possible to restrict object creation in C#? Yes, it is possible to restrict object creation in C# by using following,
Introduction C# OOP Interview Questions And Answers
C# is an Object-Oriented, functional, generic and component-oriented programming language. It is used to build a variety of applications, it is specifically strong at building Windows desktop applications and games. Web development can also be done efficiently with C# and it has increasingly become popular for mobile developments. So, it makes an excellent choice for any programmer who wishes to do web and game development. It is a statically-typed language, so written source code is thoroughly checked before it turns into an application. It is a complex language to learn and mastering it can take a substantial amount of time. There are various cross-platform tools available which allow applications written in C# which can be used over mobile and desktop.
If you are looking for a job that is related to C# OOP, you need to prepare for the 2023 C# OOP Interview Questions. Though every interview is different and the scope of a job is also different, we can help you out with the top C# OOP Interview Questions with answers, which will help you take the leap and get you success in your interview.
Below are the top 2023 C# OOP Interview Questions that are asked frequently in an interview these top questions are divided into two parts are as follows:
2 State the types of Design Patterns.
There are three types of Design Patterns-
Creational Patterns: It deals with the creation of Objects and Classes.
Structural Patterns: It deals with Class and Object Composition.
Behavioral Patterns- It deals with Class and Object Communication.Â
Part 1 – C# OOP Interview Questions (Basic)
This first part covers basic C# OOP Interview Questions and Answers
Answer: Some difference is listed below:
Answer: A delegate Object is a reference type variable that use to holds the reference to a method. The reference can be changed at runtime which is held by an object of a delegate. A delegate object can hold many functions reference which is also known as Invocation List that refers functions in a sequence FIFO, we can new functions ref in this list at runtime by a += operator and can remove by -= operator. Delegates are especially used for implementing events and the call-back methods. All delegates are implicitly derived from the System. Delegate class.
Let us move on to the next C# OOP Interview Questions
Answer: In Compile time polymorphism or Early Binding, we will use multiple methods with the same name but a different type of parameter or maybe the number or parameter because of this we can perform different-different tasks with same method name in the same class which is also known as Method overloading.
Dynamic / runtime polymorphism is also known as late binding. Here, the method name and the method signature (number of parameters and parameter type must be the same and may have a different implementation). Method overriding is an example of dynamic polymorphism.
Answer: This is the common C# OOP Interview Questions asked in an interview. if we have conflicting methods in the same class, we can’t implement their body independently in the same class because of the same name and same signature so we must use interface name before method name to remove this method confusion.
Answer: Method overloading is another name for compile-time polymorphism, where we can create a method with the same name but with a different signature. It is done at compile time and we can do it multiple ways but method name would remain the same.
A number of parameters can be different. Type of parameter can be different. Order of parameter can be different.
Example –