31
What are generics in C#?
Generics allow classes, interfaces, methods, delegates, and other types to operate with type parameters instead of being written for one specific data type.
C# Interview
Generics & Collections
C# interview questions covering generics & collections.
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32
What are generic constraints in C#?
Generic constraints restrict which types can be supplied for a generic type parameter. They allow generic code to safely use capabilities guaranteed by the constraint.
33
What is a collection in C#?
A collection is an object used to store and manage groups of values or objects. .NET provides generic collections in System.Collections.Generic for common data structures.
34
What is the difference between an array and List<T>?
An array has a fixed length after creation, while List<T> is a dynamically sized generic collection.
35
What is List<T> in C#?
List<T> is a generic, dynamically sized collection that stores elements of a specified type. It preserves insertion order and supports indexed access.
36
What is Dictionary<TKey, TValue> in C#?
Dictionary<TKey,TValue> stores data as key-value pairs. Each key must be unique, and values are retrieved using their associated keys.
37
What is IEnumerable<T> in C#?
IEnumerable<T> represents a sequence that can be enumerated one element at a time. It is the fundamental generic interface used by foreach and many LINQ operations.
38
What is the difference between IEnumerable<T> and ICollection<T>?
IEnumerable<T> provides basic sequential enumeration. ICollection<T> extends IEnumerable<T> and represents a collection that exposes additional operations and information.
39
What is the difference between IEnumerable<T> and IQueryable<T>?
IEnumerable<T> represents an enumerable sequence and its LINQ operations normally execute as .NET code over objects.
40
What are Stack<T> and Queue<T> in C#?
Stack<T> and Queue<T> are generic collections designed for different processing orders.