Mastering OOP and C# Concepts

What is the main principle of Object-Oriented Programming?

• Encapsulation of data and behavior into objects.

• Polymorphism through method overloading only.

• Static typing of all variables in the program.

• Inheritance of properties from a parent class.

In C#, what keyword is used to define a class?

• class

• function

• object

• define

What is inheritance in the context of OOP?

• Inheritance is a way to create multiple instances of a class.

• Inheritance is a method for encapsulating data within a class.

• Inheritance allows a class to override methods from another class.

• Inheritance is a mechanism in OOP where a class can inherit attributes and methods from another class.

How do you create an object of a class in C#?

• new ClassName objectName;

• ClassName objectName = ClassName();

• ClassName objectName = new ClassName();

• objectName = new ClassName();

What is polymorphism and how is it implemented in C#?

• Polymorphism in C# is implemented through method overriding and interfaces.

• Polymorphism refers to the ability to create multiple classes without any interfaces.

• Polymorphism is only achieved through inheritance in C#.

• Polymorphism in C# is implemented using static methods exclusively.

What is the purpose of the 'this' keyword in C#?

• The 'this' keyword is used to access global variables.

• The 'this' keyword is used to refer to the current instance of a class.

• The 'this' keyword is used to create new instances of a class.

• The 'this' keyword is used to declare static members of a class.

Explain the concept of encapsulation in OOP.

• Encapsulation is the bundling of data and methods that operate on that data within a single unit, restricting access to some components.

• Encapsulation refers to the inheritance of properties from one class to another.

• Encapsulation is the process of creating multiple classes for a single function.

• Encapsulation is the practice of exposing all data and methods to the public.

What is an interface in C# and how does it differ from a class?

• An interface is a type of class that can be instantiated.

• An interface in C# is a contract for methods and properties without implementation, differing from a class which can contain implementation and state.

• A class cannot have methods or properties, while an interface can.

• An interface can have implementation and state like a class.

What is the difference between a struct and a class in C#?

• Structs can inherit from other structs; classes cannot.

• Structs are value types; classes are reference types.

• Structs can have destructors; classes cannot.

• Classes are always faster than structs in performance.

How do you handle exceptions in C#?

• Ignore exceptions and continue execution.

• Use if-else statements to handle exceptions in C#.

• Use switch-case statements to handle exceptions in C#.

• Use try-catch blocks to handle exceptions in C#.