49. What is the syntax for executing a block synchronously using GCD in Objective-C?

A. dispatch_sync(dispatch_get_main_queue(), ^{ // block code here});
B. [self performSelectorOnMainThread:@selector(methodName:) withObject:nil waitUntilDone:YES];
C. There is no way to execute a block synchronously using GCD

Answer: A

50. What is the advantage of using GCD over NSThread in Objective-C?

A. GCD is a higher-level abstraction that provides better performance and memory management
B. NSThread is deprecated and should not be used
C. There is no advantage of using GCD over NSThread in Objective-C

Answer: A

Top 50 .net Interview Questions with Answers

by Ashwani KumarMay 1, 2023June 19, 2023UncategorizedLeave a Comment

1. What is .NET Framework?

a) A programming language
b) A set of libraries and runtime
c) A database management system
d) None of the above

Answer: b

2. What is CLR?

a) Common Language Runtime
b) Common Library Runtime
c) Common Line Runtime
d) None of the above

Answer: a

3. What is the use of the ‘using’ statement in C#?

a) to declare a variable
b) to include using directive
c) to denote the start of a namespace
d) to release resources

Answer: d

4. What is the difference between Value Types and Reference Types?

a) Value types store values directly in memory
b) Reference types store reference to the value in memory
c) Value types use stack to store data
d) All of the above

Answer: d

5. What is the difference between ArrayList and List in C#?

a) ArrayList can store any type of data
b) List can only store generic data
c) ArrayList can store null values
d) All of the above

Answer: b

6. What is the difference between String and StringBuilder?

a) String is immutable while StringBuilder is mutable
b) StringBuilder is faster than String for concatenation
c) String is thread-safe while StringBuilder is not
d) All of the above

Answer: a

7. What is the difference between Boxing and Unboxing in C#?

a) Boxing is converting a value type to a reference type
b) Unboxing is converting a reference type to a value type
c) Boxing and unboxing are the same
d) None of the above

Answer: a

8. What is the use of the ‘static’ keyword in C#?

a) to create static variables
b) to create static methods
c) to create a static class
d) All of the above

Answer: d

9. What is the difference between an interface and an abstract class in C#?

a) Interfaces cannot have implementation while Abstract classes can
b) A class can implement multiple interfaces but can inherit only one Abstract class
c) Both interfaces and abstract classes prevent multiple inheritance
d) All of the above

Answer: d

10. What is the use of the ‘sealed’ keyword in C#?

a) to prevent inheritance
b) to prevent overriding
c) to prevent both inheritance and overriding
d) All of the above

Answer: c

11. What is the use of the ‘finally’ block in a try-catch-finally statement?

a) to execute code when an exception is caught
b) to execute code whether an exception is caught or not
c) to prevent code from executing when an exception is caught
d) None of the above

Answer: b

12. What is the difference between a private and a protected access modifier in C#?

a) Private members can only be accessed within the same class while protected members can be accessed within the same class and its derived classes
b) Private members can only be accessed within the same assembly while protected members can be accessed within the same assembly and its derived assemblies
c) Private members can only be accessed within the same namespace while protected members can be accessed within the same namespace and its derived namespaces
d) All of the above

Answer: a

13. What is the use of the ‘yield’ keyword in C#?

a) to create an iterator
b) to break out of a loop
c) to throw an exception
d) None of the above

Answer: a

14. What is a delegate in C#?

a) a reference to a method
b) a class
c) an interface
d) None of the above

Answer: a

15. What is the use of the ‘async’ and ‘await’ keywords in C#?

a) to create asynchronous methods
b) to create synchronous methods
c) to create parallel code
d) None of the above

Answer: a

16. What is a lambda expression in C#?

a) a way to define an anonymous function
b) a way to define constants
c) a way to define classes
d) a way to define interfaces

Answer: a

17. What is the difference between an event and a delegate in C#?

a) Events are built on top of delegates
b) Delegates are methods while events are actions
c) Delegates can be invoked directly while events cannot
d) All of the above

Answer: a

18. What is a LINQ in C#?

a) Language Integrated Query
b) LINQ is a programming language
c) LINQ is a database management system
d) None of the above

Answer: a

19. What is the use of the ‘var’ keyword in C#?

a) to declare a variable
b) to declare a constant
c) to declare a property
d) None of the above

Answer: a

20. What is the difference between a try-catch statement and a try-finally statement?

a) A try-catch statement catches exceptions while a try-finally statement does not
b) A try-finally statement executes code whether or not an exception is caught
c) Both try-catch and try-finally can catch exceptions
d) All of the above

Answer: b

21. What is the difference between a ‘ref’ parameter and an ‘out’ parameter in C#?

a) ‘ref’ parameters must be initialized before being passed while ‘out’ parameters do not
b) ‘out’ parameters must be initialized before being passed while ‘ref’ parameters do not
c) Both ‘ref’ and ‘out’ parameters must be initialized before being passed
d) All of the above

Answer: b

22. What is the use of the ‘as’ operator in C#?

a) to cast objects
b) to check if an object is a certain type
c) to compare two objects for equality
d) None of the above

Answer: a

23. What is a static constructor in C#?

a) a method that is called when an instance of a class is created
b) a method that is called when a class is loaded into memory
c) a method that is called when a class is unloaded from memory
d) None of the above

Answer: b

24. What is the use of the ‘base’ keyword in C#?

a) to access the base class’ properties and methods
b) to access the derived class’ properties and methods
c) to access the base class’ constructor
d) All of the above

Answer: a

25. What is the difference between an abstract method and a virtual method in C#?

a) Abstract methods cannot have implementation while virtual methods can
b) A class must implement all abstract methods while it can choose to override virtual methods
c) Both abstract and virtual methods can have implementation
d) None of the above

Answer: b

26. What is the use of the ‘protected internal’ access modifier in C#?

a) to mark a member as protected and internal
b) to mark a member as protected or internal
c) to mark a class as protected and internal
d) None of the above

Answer: a

27. What is the use of the ‘finally’ keyword in C#?

a) to indicate the end of a try-catch-finally block
b) to indicate the start of a try-catch-finally block
c) to indicate the end of a while loop
d) None of the above

Answer: a

28. What is the use of the ‘stack’ class in C#?

a) to manage a collection of elements in a last-in, first-out manner
b) to manage a collection of elements in a first-in, first-out manner
c) to manage a collection of elements in an ordered manner
d) None of the above

Answer: a

29. What is the difference between a field and a property in C#?

a) Fields are like variables while properties are like methods
b) Properties are like variables while fields are like methods
c) Both fields and properties are like variables
d) All of the above

Answer: a

30. What is the use of the ‘using’ directive in C#?

a) to include namespace in the current file
b) to declare a variable
c) to create a namespace
d) None of the above

Answer: a

31. What is the difference between a string and a StringBuilder in C#?

a) String is immutable while StringBuilder is mutable
b) StringBuilder is faster than String for concatenation
c) String is thread-safe while StringBuilder is not
d) All of the above

Answer: a

32. What is the difference between an abstract class and an interface in C#?

Answer: d

33. What is the use of the ‘static’ keyword in C#?

a) to create static variables
b) to create static methods
c) to create a static class
d) All of the above

Answer: d

34. What is the use of the ‘sealed’ keyword in C#?

a) to prevent inheritance
b) to prevent overriding
c) to prevent both inheritance and overriding
d) All of the above

Answer: c

35. Which of the following is a value type in C#?

a) int
b) string
c) object
d) None of the above

Answer: a

36. What is the difference between an array and a List in C#?

a) Arrays have a fixed size while Lists can grow and shrink dynamically
b) Arrays can store only a single type of element while Lists can store any type of element
c) Arrays use index while Lists use iterators
d) All of the above

Answer: a

37. What is the difference between a private and a protected access modifier in C#?

Answer: a

38. What is the use of the ‘finally’ block in a try-catch-finally statement?

a) to execute code when an exception is caught
b) to execute code whether an exception is caught or not
c) to prevent code from executing when an exception is caught
d) None of the above

Answer: b

39. What is the use of the ‘yield’ keyword in C#?

a) to create an iterator
b) to break out of a loop
c) to throw an exception
d) None of the above

Answer: a

40. What is a delegate in C#?

a) a reference to a method
b) a class
c) an interface
d) None of the above

Answer: a

41. What is the use of the ‘async’ and ‘await’ keywords in C#?

a) to create asynchronous methods
b) to create synchronous methods
c) to create parallel code
d) None of the above

Answer: a

42. What is a lambda expression in C#?

a) a way to define an anonymous function
b) a way to define constants
c) a way to define classes
d) a way to define interfaces

Answer: a

43. What is the difference between an event and a delegate in C#?

a) Events are built on top of delegates
b) Delegates are methods while events are actions
c) Delegates can be invoked directly while events cannot
d) All of the above

Answer: a

44. What is the use of the ‘var’ keyword in C#?

a) to declare a variable
b) to declare a constant
c) to declare a property
d) None of the above

Answer: a

45. What is the use of the ‘base’ keyword in C#?

a) to access the base class’ properties and methods
b) to access the derived class’ properties and methods
c) to access the base class’ constructor
d) All of the above

Answer: a

46. What is the use of the ‘protected internal’ access modifier in C#?

a) to mark a member as protected and internal
b) to mark a member as protected or internal
c) to mark a class as protected and internal
d) None of the above

Answer: a

47. What is the use of the ‘stack’ class in C#?

Answer: a

48. What is the use of the ‘using’ directive in C#?

a) to include namespace in the current file
b) to declare a variable
c) to create a namespace
d) None of the above

Answer: a

49. What is the difference between a string and a StringBuilder in C#?

a) String is immutable while StringBuilder is mutable
b) StringBuilder is faster than String for concatenation
c) String is thread-safe while StringBuilder is not
d) All of the above

Answer: a

50. What is the difference between an abstract class and an interface in C#?

Answer: d

Top 50 asp.net Interview Questions with Answers

by Ashwani KumarMay 1, 2023June 19, 2023UncategorizedLeave a Comment

1. What is the full form of ASP.NET?

a) Active Server Pages .NET
b) Application Server Pages .NET
c) Advanced Server Pages .NET
d) None of the above

Answer: a) Active Server Pages .NET

2. What language is used to write ASP.NET?

a) C#
b) VB.NET
c) Both
d) None of the above

Answer: c) Both

3. What is ViewState in ASP.NET?

a) A mechanism to store and retrieve data in between postbacks
b) A way to secure data in the application
c) A process to increase the performance of the application
d) None of the above

Answer: a) A mechanism to store and retrieve data in between postbacks

4. What is the heart of the ASP.NET framework?

a) Web Forms
b) MVC
c) Web API
d) None of the above

Answer: a) Web Forms

5. Which of the following is not an advantage of ASP.NET?

a) Easy to maintain and deploy
b) Better performance
c) Good support for multiple languages
d) Expensive development tools

Answer: d) Expensive development tools

6. Which of the following is not a component of the ASP.NET architecture?

a) Web Forms
b) IIS
c) CLR
d) DBMS

Answer: d) DBMS

7. What is App_Code folder used for in an ASP.NET application?

a) To store shared resources
b) To store compiled code
c) To store configuration files
d) None of the above

Answer: b) To store compiled code

8. Which of the following is not a type of caching supported by ASP.NET?

a) Page output caching
b) Object caching
c) HttpModule caching
d) Query string caching

Answer: d) Query string caching

9. What is IIS in ASP.NET?

a) Internet Information Services
b) International Information System
c) Internet Information System
d) None of the above

Answer: a) Internet Information Services

10. What is the role of Web.config file in ASP.NET?

a) To store configuration information
b) To store user accounts
c) To store code files
d) None of the above

Answer: a) To store configuration information

11. What is the difference between Server.Transfer and Response.Redirect in ASP.NET?

a) Server.Transfer is faster than Response.Redirect
b) Server.Transfer does not redirect the user to a different page
c) Response.Redirect uses server resources
d) None of the above

Answer: b) Server.Transfer does not redirect the user to a different page

12. What is a postback in ASP.NET?

a) A request from the server for a new page
b) A request from the user for a new page
c) An event that causes the server to reload the current page
d) None of the above

Answer: c) An event that causes the server to reload the current page

13. What is the difference between GET and POST method in ASP.NET?

a) GET method is faster than POST method
b) POST method is more secure than GET method
c) GET method can’t send large amount of data
d) All of the above

Answer: b) POST method is more secure than GET method

14. What is the purpose of the Page_Load event in ASP.NET?

a) To load the page
b) To initialize the page
c) To handle postback events
d) None of the above

Answer: b) To initialize the page

15. What is a web service in ASP.NET?

a) A component that runs on a web server and provides access to its functionality through the internet
b) A component that provides access to a database
c) A component that provides access to shared resources on the network
d) None of the above

Answer: a) A component that runs on a web server and provides access to its functionality through the internet

16. What is the role of Global.asax file in ASP.NET?

a) To store configuration information
b) To handle application-level events
c) To store user accounts
d) None of the above

Answer: b) To handle application-level events

17. What is the purpose of forms authentication in ASP.NET?

a) To prevent unauthorized access to a website
b) To provide secure communication between client and server
c) To improve website performance
d) None of the above

Answer: a) To prevent unauthorized access to a website

18. Which of the following is not a type of ASP.NET control?

a) HTML control
b) Web control
c) Server control
d) User control

Answer: a) HTML control

19. What is the difference between User control and Custom control in ASP.NET?

a) User control is a reusable component while Custom control is not
b) Custom control is a reusable component while User control is not
c) Both User control and Custom control are not reusable components
d) None of the above

Answer: b) Custom control is a reusable component while User control is not

20. What is the role of Master page in ASP.NET?

a) To provide a consistent look and feel to all the pages in a website
b) To handle user authentication
c) To reduce page loading time
d) None of the above

Answer: a) To provide a consistent look and feel to all the pages in a website

21. What is URL rewriting in ASP.NET?

a) A process to redirect users to a different page
b) A process to improve website performance
c) A process to change the URL of a page
d) None of the above

Answer: c) A process to change the URL of a page

22. What is the role of the DataReader object in ADO.NET?

a) To read data from a database
b) To update data in a database
c) To insert data into a database
d) None of the above

Answer: a) To read data from a database

23. Which of the following is not a type of Data Adapter in ADO.NET?

a) OleDbDataAdapter
b) SqlDataAdapter
c) OracleDataAdapter
d) None of the above

Answer: d) None of the above

24. What is the role of the SqlCommand object in ADO.NET?

a) To execute a SQL statement
b) To open a database connection
c) To close a database connection
d) None of the above

Answer: a) To execute a SQL statement

25. Which of the following is not a type of transaction isolation level in ADO.NET?

a) ReadUncommitted
b) ReadCommitted
c) RepeatableRead
d) ReadDirty

Answer: d) ReadDirty

26. What is the role of the SqlCommandBuilder object in ADO.NET?

a) To build SQL statements dynamically
b) To create SqlCommand objects
c) To generate Update, Insert, and Delete commands automatically
d) None of the above

Answer: c) To generate Update, Insert, and Delete commands automatically

27. What is the difference between ExecuteReader and ExecuteNonQuery in ADO.NET?

a) ExecuteReader is used to read data while ExecuteNonQuery is used to execute non-query SQL statements
b) ExecuteReader is used to execute non-query SQL statements while ExecuteNonQuery is used to read data
c) Both ExecuteReader and ExecuteNonQuery are used to read data
d) None of the above

Answer: a) ExecuteReader is used to read data while ExecuteNonQuery is used to execute non-query SQL statements

28. What is the role of Data Access Layer in ASP.NET?

a) To handle database connections and transactions
b) To handle user authentication
c) To improve website performance
d) None of the above

Answer: a) To handle database connections and transactions

29. What is the role of Business Logic Layer in ASP.NET?

a) To handle database connections and transactions
b) To handle user authentication
c) To implement business rules and logic
d) None of the above

Answer: c) To implement business rules and logic

30. What is the role of Presentation Layer in ASP.NET?

a) To handle database connections and transactions
b) To handle user authentication
c) To display user interface to the user
d) None of the above

Answer: c) To display user interface to the user

31. What is the role of LINQ in ASP.NET?

a) To handle database connections and transactions
b) To implement business rules and logic
c) To query different types of data sources using a common syntax
d) None of the above

Answer: c) To query different types of data sources using a common syntax

32. What is the difference between IQueryable and IEnumerable in LINQ?

a) IQueryable is used for deferred execution while IEnumerable is used for immediate execution
b) IEnumerable is used for deferred execution while IQueryable is used for immediate execution
c) Both IQueryable and IEnumerable are used for immediate execution
d) None of the above

Answer: a) IQueryable is used for deferred execution while IEnumerable is used for immediate execution

33. What is the role of Entity Framework in ASP.NET?

a) To handle database connections and transactions
b) To implement business rules and logic
c) To provide an object-relational mapping (ORM) infrastructure
d) None of the above

Answer: c) To provide an object-relational mapping (ORM) infrastructure

34. What is the advantage of using Entity Framework in ASP.NET?

a) Reduced development time
b) Improved application performance
c) Reduced database access time
d) None of the above

Answer: a) Reduced development time

35. What is the role of ADO.NET Entity Data Model in ASP.NET?

a) To create a conceptual model of the database
b) To create a physical model of the database
c) To create a logical model of the database
d) None of the above

Answer: a) To create a conceptual model of the database

36. What is the role of LINQ to SQL in ASP.NET?

a) To handle database connections and transactions
b) To implement business rules and logic
c) To provide an object-relational mapping (ORM) infrastructure for SQL Server
d) None of the above

Answer: c) To provide an object-relational mapping (ORM) infrastructure for SQL Server

37. What is the role of ASP.NET MVC in web development?

a) To provide a flexible and modular approach to web development
b) To provide a faster response time for user requests
c) To provide a better user interface design
d) None of the above

Answer: a) To provide a flexible and modular approach to web development

38. What is the difference between ASP.NET Web Forms and ASP.NET MVC?

a) ASP.NET Web Forms uses server controls while ASP.NET MVC uses HTML controls
b) ASP.NET Web Forms provides a tightly coupled approach while ASP.NET MVC provides a loosely coupled approach
c) ASP.NET Web Forms uses script for client-side validation while ASP.NET MVC uses data annotations for client-side validation
d) None of the above

Answer: b) ASP.NET Web Forms provides a tightly coupled approach while ASP.NET MVC provides a loosely coupled approach

39. What is the role of Razor syntax in ASP.NET MVC?

a) To provide a flexible and easy to read syntax for creating views
b) To provide a way to create reusable components
c) To improve website performance
d) None of the above

Answer: a) To provide a flexible and easy to read syntax for creating views

40. What is the role of ASP.NET Web API in web development?

a) To provide a flexible and modular approach to building HTTP services
b) To provide a faster response time for user requests
c) To provide a better user interface design
d) None of the above

Answer: a) To provide a flexible and modular approach to building HTTP services

41. What is the difference between REST and SOAP in ASP.NET Web API?

a) REST uses HTTP while SOAP uses XML
b) REST is more secure than SOAP
c) SOAP provides better performance than REST
d) None of the above

Answer: a) REST uses HTTP while SOAP uses XML

42. What is the role of Dependency Injection in ASP.NET?

a) To provide a way to create modular and testable code
b) To provide a faster response time for user requests
c) To provide a better user interface design
d) None of the above

Answer: a) To provide a way to create modular and testable code

43. What is the difference between constructor injection and property injection in Dependency Injection?

a) Constructor injection requires a constructor while property injection does not
b) Property injection requires a constructor while constructor injection does not
c) Both constructor injection and property injection require a constructor
d) None of the above

Answer: a) Constructor injection requires a constructor while property injection does not

44. What is the role of NUnit in ASP.NET?

a) To provide a way to write automated unit tests in .NET
b) To provide a way to test the website performance
c) To provide a way to improve website security
d) None of the above

Answer: a) To provide a way to write automated unit tests in .NET

45. What is the role of NuGet in ASP.NET?

a) To provide a way to manage package dependencies in .NET
b) To provide a way to manage website database
c) To provide a way to manage website security
d) None of the above

Answer: a) To provide a way to manage package dependencies in .NET

46. What is the role of SignalR in ASP.NET?

a) To provide a way to create real-time web applications
b) To improve website performance
c) To provide a better user interface design
d) None of the above

Answer: a) To provide a way to create real-time web applications

47. What is the difference between HTTP and HTTPS in ASP.NET?

a) HTTPS is more secure than HTTP
b) HTTP provides better performance than HTTPS
c) HTTPS is used for public websites while HTTP is used for private websites
d) None of the above

Answer: a) HTTPS is more secure than HTTP

48. What is the role of Web API attribute routing in ASP.NET?

a) To provide a way to map HTTP requests to actions based on attributes
b) To improve website security
c) To improve website performance
d) None of the above

Answer: a) To provide a way to map HTTP requests to actions based on attributes

49. What is the difference between IQueryable and IEnumerable in Entity Framework?

Answer: a) IQueryable is used for deferred execution while IEnumerable is used for immediate execution

50. What is the role of Code First in Entity Framework?

a) To create a database based on domain classes
b) To create domain classes based on the database
c) To create a physical model of the database
d) None of the above

Answer: a) To create a database based on domain classes

Top 50 C++ Interview Questions with Answers

by Ashwani KumarMay 1, 2023June 19, 2023UncategorizedLeave a Comment

1) What is the size of a character in C++?

a) 8 bits
b) 16 bits
c) 32 bits
d) 64 bits

Answer: a) 8 bits

2) Which of the following is the correct syntax for declaring a pointer?

a) int *p;
b) *int p;
c) int p*;
d) *p int;

Answer: a) int *p;

3) What is the output of the following code?

int a = 10, b = 20;
a = a ^ b;
b = a ^ b;
a = a ^ b;
std::cout << a << ” ” << b;
a) 20 10
b) 30 20
c) 10 20
d) 20 30

Answer: a) 20 10

4) Which of the following is a correct way to allocate an integer array of size 10 on the heap?

a) int array[10];
b) int *array = new int[10]();
c) int *array = new int(10);
d) int array = new int[10];

Answer: b) int *array = new int[10]();

5) What is the output of the following code?

int x = 10, y = 5;
std::cout << (x > y ? (x < 15 ? 1 : 2) : 0);
a) 0
b) 1
c) 2
d) Compilation error

Answer: b) 1

6) Which of the following statements is true about the const keyword in C++?

a) It can be used to declare a constant variable.
b) It can be used to declare a function parameter that cannot be modified.
c) It can be used to declare a function return value that cannot be modified.
d) All of the above

Answer: d) All of the above

7) Which of the following is the correct way to declare a virtual function in C++?

a) virtual int foo();
b) virtual int foo(void);
c) virtual int foo() = 0;
d) virtual int foo() const;

Answer: a) virtual int foo();

8) Which of the following is the correct syntax to open a file in C++?

a) std::filestream myFile(“filename”, mode);
b) std::fstream myFile(“filename”, mode);
c) std::ifstream myFile(“filename”, mode);
d) Both b and c

Answer: d) Both b and c

9) What is the output of the following code?

int a = 10, b = 5;
int &refA = a, &refB = b;
refA = refB;
std::cout << a << ” ” << b;
a) 5 10
b) 10 5
c) Compilation error
d) Runtime error

Answer: a) 5 10

10) Which of the following statements about templates in C++ is true?

a) They allow generic programming in C++.
b) They provide a way to define a common functionality for different data types.
c) They can be used to define functions or classes.
d) All of the above

Answer: d) All of the above

11) Which of the following is the correct syntax to pass an array to a function in C++?

a) void func(int * arr, int size);
b) void func(int arr[], int size);
c) void func(int arr[10], int size);
d) All of the above

Answer: b) void func(int arr[], int size);

12) What is the output of the following code?

int a = 10, b = 5, c = 2;
std::cout << (a > b) << ” ” << (a < b) << ” ” << (a == b) << ” ” << (a >= c) << ” ” << (b <= c);
a) 1 0 0 1 0
b) 1 0 0 0 0
c) 0 1 0 1 1
d) Compilation error

Answer: a) 1 0 0 1 0

13) What is a destructor in C++?

a) A function that is called automatically when an object is created.
b) A function that is called automatically when an object is destroyed.
c) A function that is called manually to destroy an object.
d) A function that is used to initialize an object.

Answer: b) A function that is called automatically when an object is destroyed.

14) Which of the following is the correct syntax to define a class in C++?

a) class MyClass { public: int foo(); };
b) class MyClass() { public: int foo(); };
c) class MyClass { int foo(); };
d) class { int foo(); };

Answer: a) class MyClass { public: int foo(); };

15) What is the output of the following code?

std::cout << sizeof(“hello world”);
a) 11
b) 12
c) 13
d) Compilation error

Answer: b) 12

16) Which of the following is the correct syntax to declare an enumeration in C++?

a) enum { RED, GREEN, BLUE };
b) enum colors { RED, GREEN, BLUE };
c) enum colors { RED = 1, GREEN = 2, BLUE = 3 };
d) Both b and c

Answer: d) Both b and c

17) What is the output of the following code?

int arr[] = {1, 2, 3, 4, 5};
std::cout << sizeof(arr) / sizeof(arr[0]);
a) 1
b) 2
c) 3
d) 5

Answer: d) 5

18) What is the output of the following code?

int arr[] = {1, 2, 3, 4, 5};
int *ptr = arr;
std::cout << *ptr << ” ” << *(ptr + 3) << ” ” << *(arr + 4);
a) 1 3 5
b) 1 4 5
c) 1 4 4
d) 1 4 1

Answer: b) 1 4 5

19) What is a template specialization in C++?

a) It is a way to define a function or class for a specific data type.
b) It is a way to define a function or class for a generic data type.
c) It is a way to define a function or class for multiple data types at once.
d) It is a way to define a function or class for a derived data type.

Answer: a) It is a way to define a function or class for a specific data type.

20) Which of the following is an example of dynamic polymorphism in C++?

a) Function overloading
b) Constructor overloading
c) Operator overloading
d) Virtual functions

Answer: d) Virtual functions

21) Which of the following is not a type of inheritance in C++?

a) Public inheritance
b) Protected inheritance
c) Private inheritance
d) Multiple inheritance
e) All of the above are types of inheritance

Answer: e) All of the above are types of inheritance

22) Which of the following is the correct way to declare a member function of a class outside the class definition in C++?

a) void MyClass::foo() { }
b) void foo() { }
c) MyClass::void foo() { }
d) MyClass::foo() { }

Answer: a) void MyClass::foo() { }

23) What is the output of the following code?

int a = 10, b = 20, c;
c = a++ + –b;
std::cout << a << ” ” << b << ” ” << c;
a) 10 20 30
b) 11 20 30
c) 10 19 30
d) 11 19 30

Answer: c) 10 19 30

24) Which of the following is the correct syntax to define a destructor in C++?

a) ~ MyClass { }
b) ~MyClass() { }
c) MyClass::~() { }
d) Both a and b

Answer: b) ~MyClass() { }

25) What is the output of the following code?

int a = 10, b = 20;
std::swap(a, b);
std::cout << a << ” ” << b;
a) 10 20
b) 20 10
c) Compilation error
d) Runtime error

Answer: b) 20 10

26) Which of the following is the correct syntax to create a thread in C++?

a) std::thread myThread = new std::thread(foo);
b) std::thread myThread(foo);
c) std::thread myThread = std::thread::create(foo);
d) None of the above

Answer: b) std::thread myThread(foo);

27) What is the output of the following code?

int arr[] = {1, 2, 3, 4, 5};
for (int i : arr) {
std::cout << i << ” “;
}
a) 1 2 3 4 5
b) 5 4 3 2 1
c) Compilation error
d) Runtime error

Answer: a) 1 2 3 4 5

28) Which of the following is a correct way to include a header file in C++?

a) #include “myFile.h”
b) #include
c) #include
d) Both a and b

Answer: d) Both a and b

29) What is the output of the following code?

int arr[] = {1, 2, 3, 4, 5};
std::cout << arr << ” ” << &arr[0];
a) Same memory address
b) Different memory addresses
c) Compilation error
d) Runtime error

Answer: a) Same memory address

30) Which of the following is the correct syntax to declare a constant pointer in C++?

a) int * const ptr = &x;
b) const int * ptr = &x;
c) const int * const ptr = &x;
d) Both a and c

Answer: d) Both a and c

31) What is the output of the following code?

int arr[] = {1, 2, 3, 4, 5};
int *ptr = arr;
std::cout << arr + 4 << ” ” << ptr + 4;
a) Same memory address
b) Different memory addresses
c) Compilation error
d) Runtime error

Answer: a) Same memory address

32) Which of the following is the correct syntax for a lambda function in C++?

a) []() { }
b) [](int x) { return x * x; }
c) [x, y](int z) { return x + y + z; }
d) All of the above

Answer: d) All of the above

33) Which of the following is the correct syntax to declare a base class in C++?

a) class Base { protected: int x; }
b) class Base : protected { int x; }
c) class Base { public: int x; }
d) class Base : public { int x; }

Answer: c) class Base { public: int x; }

34) What is a singleton in C++?

a) It is a design pattern that restricts the instantiation of a class to one object.
b) It is a class that can be instantiated multiple times.
c) It is a class that is derived from another class.
d) It is a function that takes a single argument as input.

Answer: a) It is a design pattern that restricts the instantiation of a class to one object.

35) What is the output of the following code?

int a = {10}, b = {20};
std::cout << a << ” ” << b;
a) 10 20
b) {10} {20}
c) Compilation error
d) Runtime error

Answer: a) 10 20

36) Which of the following is the correct syntax for a copy constructor in C++?

a) MyClass(MyClass &obj) { }
b) MyClass(MyClass obj) { }
c) MyClass(MyClass const &obj) { }
d) Both a and c

Answer: c) MyClass(MyClass const &obj) { }

37) What is the output of the following code?

int arr[] = {1, 2, 3, 4, 5};
int *ptr = &arr[2];
std::cout << ptr[-2] << ” ” << *(ptr + 2);
a) 1 5
b) 2 4
c) Compilation error
d) Runtime error

Answer: b) 2 4

38) Which of the following is the correct syntax to call a superclass constructor in C++?

a) SuperClass();
b) SuperClass::constructor();
c) SuperClass::SuperClass();
d) Both b and c

Answer: c) SuperClass::SuperClass();

39) What is the output of the following code?

int x = 10;
int *ptr1 = &x, *ptr2 = &x;
std::cout << (ptr1 == ptr2) << ” ” << (*ptr1 == *ptr2);
a) 1 1
b) 0 0
c) 1 0
d) Compilation error

Answer: a) 1 1

40) Which of the following is the correct syntax to declare a function that takes a variable number of arguments in C++?

a) void foo(…);
b) void foo(int …);
c) void foo(int, …);
d) Both b and c

Answer: d) Both b and c

41) What is the output of the following code?

include

int foo(int x) { return x * x; }
int main() {
int arr[] = {1, 2, 3, 4, 5};
std::transform(arr, arr + 5, arr, foo);
for (int i : arr) {
std::cout << i << ” “;
}
}
a) 1 4 9 16 25
b) 1 2 3 4 5
c) Compilation error
d) Runtime error

Answer: a) 1 4 9 16 25

42) Which of the following is a correct way to declare a constant reference in C++?

a) const int & ref = x;
b) int const & ref = x;
c) Both a and b
d) None of the above

Answer: c) Both a and b

43) What is the output of the following code?

int a = 10, b = 20;
swap(a, b);
std::cout << a << ” ” << b;
a) 10 20
b) 20 10
c) Compilation error
d) Runtime error

Answer: b) 20 10

44) Which of the following is the correct syntax for a move constructor in C++?

a) MyClass(MyClass &&obj) { }
b) MyClass(MyClass obj &&) { }
c) MyClass(MyClass const &&obj) { }
d) Both a and c

Answer: a) MyClass(MyClass &&obj) { }

45) What is the output of the following code?

int a = 10, b = 20;
int *ptr1 = &a, *ptr2 = &b;
std::swap(ptr1, ptr2);
std::cout << *ptr1 << ” ” << *ptr2;
a) 10 20
b) 20 10
c) Compilation error
d) Runtime error

Answer: b) 20 10

46) Which of the following is the correct syntax to call a virtual function in C++?

a) obj.foo();
b) MyClass::foo();
c) virtual obj.foo();
d) None of the above

Answer: a) obj.foo();

47) What is the output of the following code?

int a = 10, b = 20;
int *ptr1 = &a, *ptr2 = &b;
ptr2 = ptr1;
*ptr2 = 30;
std::cout << a << ” ” << b;
a) 10 20
b) 30 20
c) Compilation error
d) Runtime error

Answer: b) 30 20

48) Which of the following is a correct way to declare a static member in C++?

a) class MyClass { public: static int x; };
b) class MyClass { static int x; public: };
c) class MyClass { static int x(); };
d) Both a and b

Answer: a) class MyClass { public: static int x; };

49) What is the output of the following code?

int a = 10, b = 2;
double c = static_cast>(a) / b;
std::cout << c;
a) 5.0
b) 5
c) 5.00
d) Compilation error

Answer: c) 5.00

50) What is a virtual destructor in C++?

a) It is a function that is called manually to destroy an object.
b) It is a function that is used to initialize an object.
c) It is a function that is called automatically when an object is destroyed.
d) It is a function that is used to create an object.

1. What is AJAX?

Answer: B

2. What is the full form of AJAX?

Answer: A

3. What is the main advantage of using AJAX?

Answer: A

4. Which HTTP request method is used in AJAX?

Answer: C

5. Which object is used to create an AJAX request?

Answer: A

6. What is the role of JSON in AJAX?

Answer: C

7. Which function is used to send an AJAX request?

Answer: A

8. Which function is used to handle AJAX response?

Answer: A

9. Which HTML tag is used to create an AJAX application?

Answer: C

10. Which file is used to handle AJAX requests in PHP?

Answer: C

11. Which function is used to encode a JavaScript object into JSON format?

Answer: C

12. Which function is used to decode a JSON string into a JavaScript object?

Answer: A

13. Which method is used to append data to a form before submitting it using AJAX?

Answer: C

14. How can you handle errors in AJAX requests?

Answer: C

15. Which web development framework has built-in support for AJAX?

Answer: C

16. What is the purpose of the XMLHttpRequest.readyState property in AJAX?

Answer: A

17. Which HTTP status code indicates a successful AJAX request?

Answer: A

18. Which method is used to cancel an AJAX request?

Answer: B

19. Which method is used to set a timeout for an AJAX request?

Answer: C

20. Which method is used to disable caching for an AJAX request?

Answer: B

21. What is the syntax for creating an AJAX request using jQuery?

Answer: A

22. Which method is used to set the data type of an AJAX response in jQuery?

Answer: A

23. Which property is used to access the response data in an AJAX request using jQuery?

Answer: A

24. Which method is used to serialize a form data in jQuery?

Answer: C

25. Which method is used to submit a form using AJAX in jQuery?

Answer: A

26. What is the syntax for creating an AJAX request using React?

Answer: B

27. Which method is used to handle errors in an AJAX request using React?

Answer: C

28. What is the purpose of the withCredentials property in AJAX requests?

Answer: A

29. Which method is used to enable cross-domain requests in AJAX?

Answer: C

30. What is the syntax for creating an AJAX request using AngularJS?

Answer: A

31. Which method is used to handle an error in an AJAX request using AngularJS?

Answer: A

32. What is the purpose of the transformRequest function in AngularJS AJAX requests?

Answer: A

33. What is the purpose of the transformResponse function in AngularJS AJAX requests?

Answer: B

34. Which method is used to cancel an AJAX request in AngularJS?

Answer: A

35. What is the syntax for creating an AJAX request using Vue.js?

Answer: A

36. Which method is used to handle an error in an AJAX request using Vue.js?

Answer: C

37. What is the purpose of the beforeRequest hook in Vue.js AJAX requests?

Answer: A

38. What is the purpose of the afterResponse hook in Vue.js AJAX requests?

Answer: B

39. Which method is used to cancel an AJAX request in Vue.js?

Answer: A

40. Which HTTP headers are used to enable caching in AJAX requests?

Answer: C