Ultimate C Sharp Test - 79+ MCQs: C# test: Evaluate Your Skills with C# Questions and Answers

1. What is 'serialization' in C#?

A process for generating random numbers in C#.

A technique for sorting arrays in C#.

A mechanism for converting an object into a stream of bytes for storage or transmission.

A way to optimize database queries in C#.

2. What is the C# operator for logical AND?

3. Which C# data type is used to represent a single character?

char

string

byte

int

4. Which data type is used to store whole numbers in C#?

double

float

int

string

5. What is the purpose of the 'is' keyword in C#?

To perform arithmetic operations

To check the type of an object

To define a new variable

To create an array

6. How do you define a property in a C# class?

property myProperty { get; set; }

int myProperty { }

function myProperty() { }

var myProperty = 10;

7. Which C# keyword is used to indicate that a class cannot be inherited from?

inherit

final

sealed

abstract

8. Which C# data type is used to store a single character?

char

string

character

letter

9. What does C# stand for?

C Sharp

C Plus

C Hash

C Number

10. What is the syntax for a single-line comment in C#?

// This is a comment

# This is a comment

-- This is a comment

/* This is a comment */

11. Which C# data type is used to represent true or false values?

bool

int

double

string

12. What is 'asynchronous programming' in C#?

A technique for running code sequentially.

A method for executing code in parallel.

A way to write code that can perform non-blocking operations and continue executing other tasks.

A way to optimize database queries in C#.

13. What is 'method overloading' in C#?

A way to override base class methods.

A technique for creating methods with the same name but different parameters in the same class.

A method for calling methods from another class.

A way to define custom operators in C#.

14. What is the purpose of the 'interface' keyword in C#?

To define a class

To create an object

To declare a constant

To define a contract for classes to implement

15. In C#, what keyword is used to define a constant?

const

constant

var

readonly

16. What is the default access modifier for class members in C# if no access modifier is specified?

public

private

protected

internal

17. What is the primary purpose of the 'using' statement in C#?

To define a new variable

To import namespaces

To create a loop

To declare a constant

18. What is the purpose of the 'finally' block in a try-catch-finally statement?

To catch exceptions

To handle errors

To execute code regardless of whether an exception is thrown or not

To define variables

19. In C#, what is the purpose of the 'using' statement?

It is used for declaring variables.

It defines a namespace for a class.

It ensures that resources are properly disposed of when no longer needed.

It specifies access modifiers for class members.

20. What keyword is used to define a method that does not return any value in C#?

void

null

none

empty

21. What is 'generics' in C#?

A way to define classes with generic parameters.

A technique for optimizing memory usage in C#.

A method for overriding base class methods.

A way to define custom attributes.

22. What is the primary benefit of using the 'async' and 'await' keywords in C#?

They improve code readability.

They allow code to run faster.

They simplify handling asynchronous operations and avoid blocking the main thread.

They enable multi-threading in C# applications.

23. What is the default access modifier for class members in C#?

public

private

protected

internal

24. Which C# keyword is used to define an enumeration?

enum

class

struct

interface

25. Which C# keyword is used to exit a method without returning a value?

break

return

exit

continue

26. Which C# data type is used to store decimal numbers with high precision?

int

double

decimal

float

27. Which C# keyword is used to handle exceptions?

try

catch

throw

exception

28. What is 'garbage collection' in C#?

A process for removing unused namespaces from code.

A method for compressing data in memory to save space.

An automatic memory management technique for reclaiming unused objects and freeing up memory.

A way to optimize database queries in C#.

29. What is a 'delegate' in C#?

A pointer to a function.

A reference to a class instance.

A collection of key-value pairs.

A keyword for declaring variables.

30. In C#, what keyword is used to create an array?

array

new

create

list

31. What is the difference between 'sealed' and 'abstract' classes in C#?

'sealed' classes cannot be inherited, while 'abstract' classes are meant to be inherited and cannot be instantiated.

'sealed' classes are meant to be inherited and cannot be instantiated, while 'abstract' classes cannot be inherited.

'sealed' classes and 'abstract' classes are the same in C#.

There is no such thing as 'sealed' or 'abstract' classes in C#.

32. Which C# keyword is used to exit a loop prematurely?

break

continue

return

exit

33. What is the purpose of the 'base' keyword in C#?

It is used to access the base class's constructor.

It is used to define a base class for inheritance.

It is used to access the base class's static members.

It is used to specify access modifiers for class members.

34. What is the C# syntax for creating a new instance of a class?

new myClass();

create myClass();

instantiate myClass();

instance myClass();

35. Which C# operator is used to perform logical AND between two Boolean values?

36. Which of the following is not a primitive data type in C#?

int

string

float

array

37. What is the purpose of the 'break' statement in a switch statement in C#?

To exit the switch statement

To continue to the next case

To skip the current case

To return a value

38. Which C# keyword is used to indicate that a method can be overridden in a derived class?

override

virtual

abstract

sealed

39. What is 'dependency injection' in C#?

A technique for injecting errors into code for testing purposes.

A method for injecting database queries into code for performance optimization.

A design pattern that allows objects to receive their dependencies from an external source rather than creating them internally.

A way to inject external libraries into a C# application.

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

class

define

struct

new

41. How do you define an array in C#?

array myArray = [1, 2, 3];

int[] myArray = {1, 2, 3};

int[] myArray = new int[3];

list myArray = [1, 2, 3];

42. What is the purpose of the 'yield' keyword in C#?

It indicates a variable is read-only.

It defines an iterator method, allowing it to yield values one at a time.

It specifies that a method should be executed asynchronously.

It declares a variable that will be lazily initialized.

43. What is the difference between 'ref' and 'out' parameters in C#?

'ref' parameters are passed by reference and must be initialized before being passed to a method, while 'out' parameters are also passed by reference but can be uninitialized.

'ref' parameters are passed by value and must be initialized before being passed to a method, while 'out' parameters are passed by reference.

'ref' parameters are used for value types, while 'out' parameters are used for reference types.

There is no difference between 'ref' and 'out' parameters in C#.

44. What is the entry point of a C# program?

main()

start()

entry()

Main()

45. What is 'nullable types' in C#?

Types that cannot be assigned a value.

Types that are automatically initialized to null.

Types that can represent both a value and a lack of a value (null).

Types that have fixed size and cannot be resized.

46. What is 'attribute-based programming' in C#?

A technique for hiding code from external access.

A method for obfuscating code in C#.

A way to define custom attributes and apply them to code elements for additional metadata and behavior.

A way to define classes with attributes instead of methods.

47. What is the purpose of the 'using' directive in a C# program?

To declare variables

To define classes

To import namespaces

To create objects

48. What is 'reflection' in C#?

It is a feature that allows classes to inherit from multiple base classes.

It is a technique for creating dynamic objects at runtime.

It is a mechanism for examining and interacting with the metadata of types, objects, and assemblies.

It is a way to implement garbage collection in C#.

49. How do you define a static method in a C# class?

static void myMethod() { }

void static myMethod() { }

public myMethod() { }

static public void myMethod() { }

50. What is the purpose of the 'volatile' keyword in C#?

It indicates that a variable cannot be modified.

It specifies a variable's data type.

It ensures that variable access is synchronized between multiple threads.

It defines a constant value.

C# MCQ Test 1