Data Collections

Question 1

What is the primary purpose of data collections in C# .Net?

Answer 1

To store and manage groups of related data.

Question 2

True or False: Arrays in C# are fixed in size after they are created.

Answer 2

True.

Question 3

Fill in the blank: The __________ collection is used for storing key-value pairs.

Answer 3

Dictionary.

Question 4

What is the main difference between List<T> and Array in C#?</T>

Answer 4

List<T> is dynamic in size while Array is fixed in size.</T>

Question 5

Which data collection type would you use for a collection that requires unique elements?

Answer 5

HashSet.

Question 6

What interface do all collection types in C# implement?

Answer 6

IEnumerable.

Question 7

True or False: A Queue in C# follows a Last In First Out (LIFO) order.

Answer 7

False.

Question 8

What collection type is best suited for implementing a stack in C#?

Answer 8

Stack<T>.</T>

Question 9

What does the ‘T’ represent in List<T>?</T>

Answer 9

Type parameter.

Question 10

Which collection allows duplicates and maintains the order of elements?

Answer 10

List<T>.</T>

Question 11

What is the primary use of the ConcurrentBag<T> collection?</T>

Answer 11

To store a collection of objects that can be accessed by multiple threads.

Question 12

Fill in the blank: A __________ is a collection that can be accessed in a thread-safe manner.

Answer 12

Concurrent collection.

Question 13

What collection type would you use for a first-in, first-out (FIFO) access pattern?

Answer 13

Queue<T>.</T>

Question 14

True or False: The Dictionary<TKey, TValue> collection allows duplicate keys.

Answer 14

False.

Question 15

What method is used to add an element to a List<T>?</T>

Answer 15

Add().

Question 16

Which collection type is best for implementing a lookup table?

Answer 16

Dictionary<TKey, TValue>.

Question 17

What is the default capacity of a List<T> when it is created?</T>

Answer 17

0.

Question 18

True or False: A LinkedList<T> allows access to elements by index.</T>

Answer 18

False.

Question 19

What is the time complexity of accessing an element in a List<T> by index?</T>

Answer 19

O(1).

Question 20

What collection would you use to store a fixed-size collection of objects?

Answer 20

Array.

Question 21

Fill in the blank: The __________ class provides a way to store a collection of objects in a sorted order.

Answer 21

SortedList.

Question 22

What is the primary advantage of using a HashSet?

Answer 22

It provides fast lookup times for unique elements.

Question 23

Which method removes all elements from a collection in C#?

Answer 23

Clear().

Question 24

True or False: A Stack<T> allows random access to elements.</T>

Answer 24

False.

Question 25

What is the purpose of the IEnumerable interface?

Answer 25

It allows iteration over a collection.

Question 26

Which collection type is ideal for storing items with a unique identifier?

Answer 26

Dictionary.

Question 27

Fill in the blank: The __________ method is used to sort elements in a List.

Answer 27

Sort().

Question 28

What collection type can automatically resize itself as elements are added?

Answer 28

List.

Question 29

True or False: The ArrayList class is type-safe.

Answer 29

False.

Question 30

What does the 'Contains' method do in a collection?

Answer 30

It checks if a specific element is present in the collection.

Question 31

Which collection is best suited for implementing a priority queue?

Answer 31

SortedSet.

Question 32

What is the time complexity of adding an element to a HashSet?

Answer 32

O(1) on average.

Question 33

True or False: You can use the foreach loop to iterate over a List.

Answer 33

True.

Question 34

What collection would you use for a collection of objects that need to be ordered but can contain duplicates?

Answer 34

List.

Question 35

Fill in the blank: The __________ class is designed for storing data in a key-value pair format.

Answer 35

Dictionary.

Question 36

What is a key characteristic of the Queue collection?

Answer 36

It follows FIFO order.

Question 37

Which collection type is best for scenarios involving frequent additions and removals?

Answer 37

LinkedList.

Question 38

True or False: A Dictionary can be iterated using a foreach loop.

Answer 38

True.

Question 39

What method would you use to find the index of an element in a List?

Answer 39

IndexOf().

Question 40

What does the 'AddRange' method do in a List?

Answer 40

It adds multiple elements to the List at once.

Question 41

Which collection type is not designed for concurrent access?

Answer 41

List.

Question 42

Fill in the blank: The __________ class is a generic collection that stores elements in a sorted order.

Answer 42

SortedSet.

Question 43

What is the primary use of the ObservableCollection?

Answer 43

To provide notifications when items are added, removed, or the entire list is refreshed.

Question 44

True or False: The List class implements the IList interface.

Answer 44

True.

Question 45

What collection would you choose for a simple list of items with no specific order?

Answer 45

List.