Namespace: System.Collections.Generic

List<T>

<T>

Represents a strongly typed list of objects that can be accessed by index. Provides methods for manipulating the list.

Table of Contents

Constructors

  • List()
    public List<T>()

    Initializes a new instance of the List<T> class that is empty, has the default initial capacity, and uses the default equality comparer for the type of the elements.

  • List(int capacity)
    public List<T>(int capacity)

    Initializes a new instance of the List<T> class that is empty and has the specified initial capacity.

    capacity: The number of elements that the new list can initially store.
  • List(IEnumerable<T> collection)
    public List<T>(IEnumerable<T> collection)

    Initializes a new instance of the List<T> class that contains elements copied from the specified collection and has enough capacity to accommodate the number of elements copied.

    collection: The collection whose elements are copied to the new list.

Properties

  • Capacity
    public int Capacity { get; set; }

    Gets or sets the number of elements that the List<T> can contain.

  • Count
    public int Count { get; }

    Gets the number of elements actually contained in the List<T>.

  • Item
    public T this[int index] { get; set; }

    Gets or sets the element at the specified index.

    index: The zero-based index of the element to get or set.

Methods

  • Add
    public void Add(T item)

    Adds an object to the end of the List<T>.

    item: The object to be added to the List<T>. The value can be null for reference types.
  • AddRange
    public void AddRange(IEnumerable<T> collection)

    Appends the elements of the specified collection to the end of the List<T>.

    collection: The collection whose elements should be added to the end of the List<T>. Applications that need to support the collection of ICollection<T> objects should use the parameter type and not the base interface type.
  • Clear
    public void Clear()

    Removes all elements from the List<T>.

  • Contains
    public bool Contains(T item)

    Determines whether an element is in the List<T>.

    item: The object to locate in the List<T>. The value can be null for reference types.

    Returns: true if item is found in the List<T>; otherwise, false.

  • Exists
    public bool Exists(Predicate<T> match)

    Determines whether any element of the current List<T> matches the specified condition.

    match: The condition to test for each element. The value of this parameter must not be null.

    Returns: true if the list contains one or more elements that match the specified condition; otherwise, false.

  • Find
    public T Find(Predicate<T> match)

    Searches for an element that matches the specified condition and returns the zero-based index of the first occurrence within the entire List<T>.

    match: The condition to test for each element. The value of this parameter must not be null.

    Returns: The zero-based index of the first occurrence of the element that matches the condition, or -1 if no such element is found.

  • FindAll
    public List<T> FindAll(Predicate<T> match)

    Implements the IList<T>.Insert method.

    match: The condition to test for each element. The value of this parameter must not be null.

    Returns: A List<T> containing all the elements that match the specified condition.

  • IndexOf
    public int IndexOf(T item)

    Searches for the specified object and returns the zero-based index of the first occurrence within the entire List<T>.

    item: The object to locate in the List<T>. The value can be null for reference types.

    Returns: The zero-based index of the first occurrence of item within the entire List<T>, or -1 if there are no occurrences or the item is not present.

  • Insert
    public void Insert(int index, T item)

    Inserts an element into the List<T> at the specified index.

    index: The zero-based index at which item should be inserted. item: The object to insert into the List<T>. The value can be null for reference types.
  • Remove
    public bool Remove(T item)

    Removes the first occurrence of a specific object from the List<T>.

    item: The object to remove from the List<T>. The value can be null for reference types.

    Returns: true if item is successfully removed from the List<T>; otherwise, false. This method also returns false if item is not found in the original List<T>.

  • RemoveAt
    public void RemoveAt(int index)

    Removes the element at the specified index of the List<T>.

    index: The zero-based index of the element to remove.
  • Sort
    public void Sort()

    Sorts the elements in the entire List<T> using the default comparer.

  • ToArray
    public T[] ToArray()

    Copies the entire List<T> to a new one-dimensional Array, using the array's zero-based index.

    Returns: A one-dimensional Array containing the elements of the List<T>.

Events

  • This type implements no events.

Interfaces

  • System.Collections.IList<T>
  • System.Collections.Generic.IReadOnlyList<T>
  • System.Collections.ICollection
  • System.Collections.Generic.ICollection<T>
  • System.Collections.IEnumerable
  • System.Collections.Generic.IEnumerable<T>