C# Collections

In C#, collections are used to store and manipulate groups of objects. They provide various data structures and algorithms to efficiently organize, access, and modify data. C# offers several built-in collection classes that you can use depending on your specific requirements. Here are some commonly used collection classes in C#:

  1. Array: An array is a fixed-size collection of elements of the same type. The length of an array is determined at the time of creation and cannot be changed later.
  2. List<T>: List<T> is a dynamic-size collection that can grow or shrink as needed. It is implemented as an array internally, but provides additional methods for easy manipulation of elements.
  3. Dictionary<TKey, TValue>: Dictionary<TKey, TValue> is a collection of key-value pairs. It allows fast lookup and retrieval of values based on unique keys. Keys must be unique within the dictionary.
  4. HashSet<T>: HashSet<T> is an unordered collection of unique elements. It provides fast insertion, deletion, and lookup operations.
  5. Queue<T>: Queue<T> is a first-in, first-out (FIFO) collection. It allows adding elements to the end and removing elements from the beginning.
  6. Stack<T>: Stack<T> is a last-in, first-out (LIFO) collection. It allows adding elements to the top and removing elements from the top.
  7. LinkedList<T>: LinkedList<T> is a doubly linked list implementation. It allows efficient insertion, removal, and traversal of elements.
  8. SortedSet<T>: SortedSet<T> is a sorted collection of unique elements. It maintains the elements in sorted order, allowing efficient searching and retrieval operations.
  9. SortedDictionary<TKey, TValue>: SortedDictionary<TKey, TValue> is a sorted collection of key-value pairs. It maintains the elements sorted by key, enabling fast searching and retrieval.
  10. ObservableCollection<T>: ObservableCollection<T> is a collection class that implements the INotifyCollectionChanged interface. It provides notifications when the collection changes, allowing data binding in user interfaces.

These are just a few examples of the collection classes available in C#. Each collection class has its own set of methods and properties for manipulating and accessing the stored data. You can choose the appropriate collection class based on your specific needs and the desired behavior of your program.