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System.Collections.LinkedList<T> Class

Represents a doubly linked list of objects.

Namespace

System.Collections

Assembly

System.dll

Syntax

public class LinkedList<T> : ICollection, IEnumerable

Remarks

A LinkedList<T> is a collection that contains nodes. Each node in the list contains a reference to its predecessor and successor. A LinkedList<T> is useful when you need to frequently insert or remove elements from the beginning or end of the list, or when you need to access elements from both ends.

The LinkedList<T> provides methods for adding, removing, and finding elements. It also provides an enumerator that can traverse the list.

Fields

There are no public fields for this class.

Properties

Name	Description
`Count`	Gets the number of elements actually contained in the `LinkedList<T>`.
`First`	Gets the first node of the `LinkedList<T>`.
`Last`	Gets the last node of the `LinkedList<T>`.

Methods

Name	Description
`AddAfter`	Adds a new node with the specified value after the specified node.
`AddBefore`	Adds a new node with the specified value before the specified node.
`AddFirst`	Adds a new node at the beginning of the `LinkedList<T>`.
`AddLast`	Adds a new node at the end of the `LinkedList<T>`.
`Clear`	Removes all nodes from the `LinkedList<T>`.
`Contains`	Determines whether an element is in the `LinkedList<T>`.
`CopyTo`	Copies the entire `LinkedList<T>` to a compatible one-dimensional `Array`, starting at the specified index of the target array.
`Find`	Searches for the specified element and returns the first occurrence within the entire `LinkedList<T>`.
`FindLast`	Searches for the specified element and returns the last occurrence within the entire `LinkedList<T>`.
`Remove`	Removes the first occurrence of the specified value from the `LinkedList<T>`.
`Remove`	Removes the specified node from the `LinkedList<T>`.
`RemoveAll`	Removes all the elements that match the conditions defined by the specified predicate.
`RemoveFirst`	Removes the first node from the `LinkedList<T>`.
`RemoveLast`	Removes the last node from the `LinkedList<T>`.

Example

Creating and Manipulating a LinkedList

The following example demonstrates how to create a LinkedList<T>, add elements to it, and traverse its nodes.

using System;
using System.Collections.Generic;

public class LinkedListExample
{
    public static void Main(string[] args)
    {
        // Create a LinkedList of strings
        LinkedList<string> names = new LinkedList<string>();

        // Add nodes to the end of the list
        names.AddLast("Alice");
        names.AddLast("Bob");

        // Add nodes to the beginning of the list
        names.AddFirst("Charlie");
        names.AddFirst("David");

        // Output the list
        Console.WriteLine("Initial list:");
        foreach (string name in names)
        {
            Console.WriteLine(name);
        }
        // Expected output:
        // David
        // Charlie
        // Alice
        // Bob

        // Find a node
        LinkedListNode<string> aliceNode = names.Find("Alice");

        // Add a node after "Alice"
        if (aliceNode != null)
        {
            names.AddAfter(aliceNode, "Eve");
        }

        // Remove "Bob"
        names.Remove("Bob");

        // Output the modified list
        Console.WriteLine("\nModified list:");
        foreach (string name in names)
        {
            Console.WriteLine(name);
        }
        // Expected output:
        // David
        // Charlie
        // Alice
        // Eve

        Console.WriteLine($"\nList count: {names.Count}"); // Expected output: 4
        Console.WriteLine($"First element: {names.First.Value}"); // Expected output: David
        Console.WriteLine($"Last element: {names.Last.Value}"); // Expected output: Eve
    }
}

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