List<T> Constructores

Definición

Inicializa una nueva instancia de la clase List<T>.Initializes a new instance of the List<T> class.

Sobrecargas

List<T>()

Inicializa una nueva instancia de la clase List<T> que está vacía y tiene la capacidad inicial predeterminada.Initializes a new instance of the List<T> class that is empty and has the default initial capacity.

List<T>(IEnumerable<T>)

Inicializa una nueva instancia de la clase List<T> que contiene elementos copiados de la colección especificada y tiene una capacidad suficiente para aceptar el número de elementos copiados.Initializes a new instance of the List<T> class that contains elements copied from the specified collection and has sufficient capacity to accommodate the number of elements copied.

List<T>(Int32)

Inicializa una nueva instancia de la clase List<T> que está vacía y tiene la capacidad inicial especificada.Initializes a new instance of the List<T> class that is empty and has the specified initial capacity.

List<T>()

Inicializa una nueva instancia de la clase List<T> que está vacía y tiene la capacidad inicial predeterminada.Initializes a new instance of the List<T> class that is empty and has the default initial capacity.

public:
 List();
public List ();
Public Sub New ()

Ejemplos

En el ejemplo siguiente se muestra el constructor sin parámetros de la List<T> clase genérica.The following example demonstrates the parameterless constructor of the List<T> generic class. El constructor sin parámetros crea una lista con la capacidad predeterminada, como se muestra al mostrar la Capacity propiedad.The parameterless constructor creates a list with the default capacity, as demonstrated by displaying the Capacity property.

En el ejemplo se agregan, insertan y quitan elementos, mostrando cómo cambia la capacidad cuando se usan estos métodos.The example adds, inserts, and removes items, showing how the capacity changes as these methods are used.

using namespace System;
using namespace System::Collections::Generic;

void main()
{
    List<String^>^ dinosaurs = gcnew List<String^>();

    Console::WriteLine("\nCapacity: {0}", dinosaurs->Capacity);

    dinosaurs->Add("Tyrannosaurus");
    dinosaurs->Add("Amargasaurus");
    dinosaurs->Add("Mamenchisaurus");
    dinosaurs->Add("Deinonychus");
    dinosaurs->Add("Compsognathus");

    Console::WriteLine();
    for each(String^ dinosaur in dinosaurs )
    {
        Console::WriteLine(dinosaur);
    }

    Console::WriteLine("\nCapacity: {0}", dinosaurs->Capacity);
    Console::WriteLine("Count: {0}", dinosaurs->Count);

    Console::WriteLine("\nContains(\"Deinonychus\"): {0}",
        dinosaurs->Contains("Deinonychus"));

    Console::WriteLine("\nInsert(2, \"Compsognathus\")");
    dinosaurs->Insert(2, "Compsognathus");

    Console::WriteLine();
    for each(String^ dinosaur in dinosaurs )
    {
        Console::WriteLine(dinosaur);
    }

    Console::WriteLine("\ndinosaurs[3]: {0}", dinosaurs[3]);

    Console::WriteLine("\nRemove(\"Compsognathus\")");
    dinosaurs->Remove("Compsognathus");

    Console::WriteLine();
    for each(String^ dinosaur in dinosaurs )
    {
        Console::WriteLine(dinosaur);
    }

    dinosaurs->TrimExcess();
    Console::WriteLine("\nTrimExcess()");
    Console::WriteLine("Capacity: {0}", dinosaurs->Capacity);
    Console::WriteLine("Count: {0}", dinosaurs->Count);

    dinosaurs->Clear();
    Console::WriteLine("\nClear()");
    Console::WriteLine("Capacity: {0}", dinosaurs->Capacity);
    Console::WriteLine("Count: {0}", dinosaurs->Count);
}

/* This code example produces the following output:

Capacity: 0

Tyrannosaurus
Amargasaurus
Mamenchisaurus
Deinonychus
Compsognathus

Capacity: 8
Count: 5

Contains("Deinonychus"): True

Insert(2, "Compsognathus")

Tyrannosaurus
Amargasaurus
Compsognathus
Mamenchisaurus
Deinonychus
Compsognathus

dinosaurs[3]: Mamenchisaurus

Remove("Compsognathus")

Tyrannosaurus
Amargasaurus
Mamenchisaurus
Deinonychus
Compsognathus

TrimExcess()
Capacity: 5
Count: 5

Clear()
Capacity: 5
Count: 0
 */
List<string> dinosaurs = new List<string>();

Console.WriteLine("\nCapacity: {0}", dinosaurs.Capacity);

dinosaurs.Add("Tyrannosaurus");
dinosaurs.Add("Amargasaurus");
dinosaurs.Add("Mamenchisaurus");
dinosaurs.Add("Deinonychus");
dinosaurs.Add("Compsognathus");
Console.WriteLine();
foreach(string dinosaur in dinosaurs)
{
    Console.WriteLine(dinosaur);
}

Console.WriteLine("\nCapacity: {0}", dinosaurs.Capacity);
Console.WriteLine("Count: {0}", dinosaurs.Count);

Console.WriteLine("\nContains(\"Deinonychus\"): {0}",
    dinosaurs.Contains("Deinonychus"));

Console.WriteLine("\nInsert(2, \"Compsognathus\")");
dinosaurs.Insert(2, "Compsognathus");

Console.WriteLine();
foreach(string dinosaur in dinosaurs)
{
    Console.WriteLine(dinosaur);
}

// Shows accessing the list using the Item property.
Console.WriteLine("\ndinosaurs[3]: {0}", dinosaurs[3]);

Console.WriteLine("\nRemove(\"Compsognathus\")");
dinosaurs.Remove("Compsognathus");

Console.WriteLine();
foreach(string dinosaur in dinosaurs)
{
    Console.WriteLine(dinosaur);
}

dinosaurs.TrimExcess();
Console.WriteLine("\nTrimExcess()");
Console.WriteLine("Capacity: {0}", dinosaurs.Capacity);
Console.WriteLine("Count: {0}", dinosaurs.Count);

dinosaurs.Clear();
Console.WriteLine("\nClear()");
Console.WriteLine("Capacity: {0}", dinosaurs.Capacity);
Console.WriteLine("Count: {0}", dinosaurs.Count);

/* This code example produces the following output:

Capacity: 0

Tyrannosaurus
Amargasaurus
Mamenchisaurus
Deinonychus
Compsognathus

Capacity: 8
Count: 5

Contains("Deinonychus"): True

Insert(2, "Compsognathus")

Tyrannosaurus
Amargasaurus
Compsognathus
Mamenchisaurus
Deinonychus
Compsognathus

dinosaurs[3]: Mamenchisaurus

Remove("Compsognathus")

Tyrannosaurus
Amargasaurus
Mamenchisaurus
Deinonychus
Compsognathus

TrimExcess()
Capacity: 5
Count: 5

Clear()
Capacity: 5
Count: 0
 */
Imports System.Collections.Generic

Public Class Example

    Public Shared Sub Main()
        Dim dinosaurs As New List(Of String)

        Console.WriteLine(vbLf & "Capacity: {0}", dinosaurs.Capacity)

        dinosaurs.Add("Tyrannosaurus")
        dinosaurs.Add("Amargasaurus")
        dinosaurs.Add("Mamenchisaurus")
        dinosaurs.Add("Deinonychus")
        dinosaurs.Add("Compsognathus")

        Console.WriteLine()
        For Each dinosaur As String In dinosaurs
            Console.WriteLine(dinosaur)
        Next

        Console.WriteLine(vbLf & "Capacity: {0}", dinosaurs.Capacity)
        Console.WriteLine("Count: {0}", dinosaurs.Count)

        Console.WriteLine(vbLf & "Contains(""Deinonychus""): {0}", _
            dinosaurs.Contains("Deinonychus"))

        Console.WriteLine(vbLf & "Insert(2, ""Compsognathus"")")
        dinosaurs.Insert(2, "Compsognathus")

        Console.WriteLine()
        For Each dinosaur As String In dinosaurs
            Console.WriteLine(dinosaur)
        Next
        ' Shows how to access the list using the Item property.
        Console.WriteLine(vbLf & "dinosaurs(3): {0}", dinosaurs(3))
        Console.WriteLine(vbLf & "Remove(""Compsognathus"")")
        dinosaurs.Remove("Compsognathus")

        Console.WriteLine()
        For Each dinosaur As String In dinosaurs
            Console.WriteLine(dinosaur)
        Next

        dinosaurs.TrimExcess()
        Console.WriteLine(vbLf & "TrimExcess()")
        Console.WriteLine("Capacity: {0}", dinosaurs.Capacity)
        Console.WriteLine("Count: {0}", dinosaurs.Count)

        dinosaurs.Clear()
        Console.WriteLine(vbLf & "Clear()")
        Console.WriteLine("Capacity: {0}", dinosaurs.Capacity)
        Console.WriteLine("Count: {0}", dinosaurs.Count)
    End Sub
End Class

' This code example produces the following output:
'
'Capacity: 0
'
'Tyrannosaurus
'Amargasaurus
'Mamenchisaurus
'Deinonychus
'Compsognathus
'
'Capacity: 8
'Count: 5
'
'Contains("Deinonychus"): True
'
'Insert(2, "Compsognathus")
'
'Tyrannosaurus
'Amargasaurus
'Compsognathus
'Mamenchisaurus
'Deinonychus
'Compsognathus
'
'dinosaurs(3): Mamenchisaurus
'
'Remove("Compsognathus")
'
'Tyrannosaurus
'Amargasaurus
'Mamenchisaurus
'Deinonychus
'Compsognathus
'
'TrimExcess()
'Capacity: 5
'Count: 5
'
'Clear()
'Capacity: 5
'Count: 0

[<EntryPoint>]
let main argv = 
    // We refer to System.Collections.Generic.List<'T> by its type 
    // abbreviation ResizeArray<'T> to avoid conflict with the List module.    
    // Note: In F# code, F# linked lists are usually preferred over
    // ResizeArray<'T> when an extendable collection is required.
    let dinosaurs = ResizeArray<_>()
 
    // Write out the dinosaurs in the ResizeArray.
    let printDinosaurs() =
        printfn ""
        dinosaurs |> Seq.iter (fun p -> printfn "%O" p) 
 
    
    printfn "\nCapacity: %i" dinosaurs.Capacity
 
    dinosaurs.Add("Tyrannosaurus")
    dinosaurs.Add("Amargasaurus")
    dinosaurs.Add("Mamenchisaurus")
    dinosaurs.Add("Deinonychus")
    dinosaurs.Add("Compsognathus")
 
    printDinosaurs()
 
    printfn "\nCapacity: %i" dinosaurs.Capacity
    printfn "Count: %i" dinosaurs.Count
 
    printfn "\nContains(\"Deinonychus\"): %b" (dinosaurs.Contains("Deinonychus"))
 
    printfn "\nInsert(2, \"Compsognathus\")"
    dinosaurs.Insert(2, "Compsognathus")
 
    printDinosaurs()
 
    // Shows accessing the list using the Item property.
    printfn "\ndinosaurs[3]: %s" dinosaurs.[3]
 
    printfn "\nRemove(\"Compsognathus\")"
    dinosaurs.Remove("Compsognathus") |> ignore
 
    printDinosaurs()
 
    dinosaurs.TrimExcess()
    printfn "\nTrimExcess()"
    printfn "Capacity: %i" dinosaurs.Capacity
    printfn "Count: %i" dinosaurs.Count
 
    dinosaurs.Clear()
    printfn "\nClear()"
    printfn "Capacity: %i" dinosaurs.Capacity
    printfn "Count: %i" dinosaurs.Count
 
    0 // return an integer exit code
 
    (* This code example produces the following output:
 
Capacity: 0
 
Tyrannosaurus
Amargasaurus
Mamenchisaurus
Deinonychus
Compsognathus
 
Capacity: 8
Count: 5
 
Contains("Deinonychus"): true
 
Insert(2, "Compsognathus")
 
Tyrannosaurus
Amargasaurus
Compsognathus
Mamenchisaurus
Deinonychus
Compsognathus
 
dinosaurs[3]: Mamenchisaurus
 
Remove("Compsognathus")
 
Tyrannosaurus
Amargasaurus
Mamenchisaurus
Deinonychus
Compsognathus
 
TrimExcess()
Capacity: 5
Count: 5
 
Clear()
Capacity: 5
Count: 0
    *)

Comentarios

La capacidad de List<T> es el número de elementos que List<T> puede contener.The capacity of a List<T> is the number of elements that the List<T> can hold. A medida que se agregan elementos a una List<T> , la capacidad aumenta automáticamente según sea necesario reasignando la matriz interna.As elements are added to a List<T>, the capacity is automatically increased as required by reallocating the internal array.

Si se puede calcular el tamaño de la colección, el uso del List<T>(Int32) constructor y la especificación de la capacidad inicial elimina la necesidad de realizar una serie de operaciones de cambio de tamaño al agregar elementos a List<T> .If the size of the collection can be estimated, using the List<T>(Int32) constructor and specifying the initial capacity eliminates the need to perform a number of resizing operations while adding elements to the List<T>.

La capacidad se puede reducir llamando al TrimExcess método o estableciendo la Capacity propiedad explícitamente.The capacity can be decreased by calling the TrimExcess method or by setting the Capacity property explicitly. Al reducir la capacidad, se reasigna la memoria y se copian todos los elementos de List<T> .Decreasing the capacity reallocates memory and copies all the elements in the List<T>.

Este constructor es una operación O (1).This constructor is an O(1) operation.

Se aplica a

List<T>(IEnumerable<T>)

Inicializa una nueva instancia de la clase List<T> que contiene elementos copiados de la colección especificada y tiene una capacidad suficiente para aceptar el número de elementos copiados.Initializes a new instance of the List<T> class that contains elements copied from the specified collection and has sufficient capacity to accommodate the number of elements copied.

public:
 List(System::Collections::Generic::IEnumerable<T> ^ collection);
public List (System.Collections.Generic.IEnumerable<T> collection);
new System.Collections.Generic.List<'T> : seq<'T> -> System.Collections.Generic.List<'T>
Public Sub New (collection As IEnumerable(Of T))

Parámetros

collection
IEnumerable<T>

Colección cuyos elementos se copian en la nueva lista.The collection whose elements are copied to the new list.

Excepciones

collection es null.collection is null.

Ejemplos

En el ejemplo siguiente se muestra el List<T> constructor y varios métodos de la List<T> clase que actúan en intervalos.The following example demonstrates the List<T> constructor and various methods of the List<T> class that act on ranges. Una matriz de cadenas se crea y se pasa al constructor, rellenando la lista con los elementos de la matriz.An array of strings is created and passed to the constructor, populating the list with the elements of the array. CapacityA continuación, se muestra la propiedad para mostrar que la capacidad inicial es exactamente lo que se necesita para contener los elementos de entrada.The Capacity property is then displayed, to show that the initial capacity is exactly what is required to hold the input elements.

using namespace System;
using namespace System::Collections::Generic;

void main()
{
    array<String^>^ input = { "Brachiosaurus", 
                              "Amargasaurus", 
                              "Mamenchisaurus" };

    List<String^>^ dinosaurs = 
        gcnew List<String^>((IEnumerable<String^>^) input);

    Console::WriteLine("\nCapacity: {0}", dinosaurs->Capacity);

    Console::WriteLine();
    for each(String^ dinosaur in dinosaurs )
    {
        Console::WriteLine(dinosaur);
    }

    Console::WriteLine("\nAddRange(dinosaurs)");
    dinosaurs->AddRange(dinosaurs);

    Console::WriteLine();
    for each(String^ dinosaur in dinosaurs )
    {
        Console::WriteLine(dinosaur);
    }

    Console::WriteLine("\nRemoveRange(2, 2)");
    dinosaurs->RemoveRange(2, 2);

    Console::WriteLine();
    for each(String^ dinosaur in dinosaurs )
    {
        Console::WriteLine(dinosaur);
    }

    input = gcnew array<String^> { "Tyrannosaurus", 
                                   "Deinonychus", 
                                   "Velociraptor"};

    Console::WriteLine("\nInsertRange(3, (IEnumerable<String^>^) input)");
    dinosaurs->InsertRange(3, (IEnumerable<String^>^) input);

    Console::WriteLine();
    for each(String^ dinosaur in dinosaurs )
    {
        Console::WriteLine(dinosaur);
    }

    Console::WriteLine("\noutput = dinosaurs->GetRange(2, 3)->ToArray()");
    array<String^>^ output = dinosaurs->GetRange(2, 3)->ToArray();
        
    Console::WriteLine();
    for each(String^ dinosaur in output )
    {
        Console::WriteLine(dinosaur);
    }
}

/* This code example produces the following output:

Capacity: 3

Brachiosaurus
Amargasaurus
Mamenchisaurus

AddRange(dinosaurs)

Brachiosaurus
Amargasaurus
Mamenchisaurus
Brachiosaurus
Amargasaurus
Mamenchisaurus

RemoveRange(2, 2)

Brachiosaurus
Amargasaurus
Amargasaurus
Mamenchisaurus

InsertRange(3, (IEnumerable<String^>^) input)

Brachiosaurus
Amargasaurus
Amargasaurus
Tyrannosaurus
Deinonychus
Velociraptor
Mamenchisaurus

output = dinosaurs->GetRange(2, 3)->ToArray()

Amargasaurus
Tyrannosaurus
Deinonychus
 */
using System;
using System.Collections.Generic;

public class Example
{
    public static void Main()
    {
        string[] input = { "Brachiosaurus",
                           "Amargasaurus",
                           "Mamenchisaurus" };

        List<string> dinosaurs = new List<string>(input);

        Console.WriteLine("\nCapacity: {0}", dinosaurs.Capacity);

        Console.WriteLine();
        foreach( string dinosaur in dinosaurs )
        {
            Console.WriteLine(dinosaur);
        }

        Console.WriteLine("\nAddRange(dinosaurs)");
        dinosaurs.AddRange(dinosaurs);

        Console.WriteLine();
        foreach( string dinosaur in dinosaurs )
        {
            Console.WriteLine(dinosaur);
        }

        Console.WriteLine("\nRemoveRange(2, 2)");
        dinosaurs.RemoveRange(2, 2);

        Console.WriteLine();
        foreach( string dinosaur in dinosaurs )
        {
            Console.WriteLine(dinosaur);
        }

        input = new string[] { "Tyrannosaurus",
                               "Deinonychus",
                               "Velociraptor"};

        Console.WriteLine("\nInsertRange(3, input)");
        dinosaurs.InsertRange(3, input);

        Console.WriteLine();
        foreach( string dinosaur in dinosaurs )
        {
            Console.WriteLine(dinosaur);
        }

        Console.WriteLine("\noutput = dinosaurs.GetRange(2, 3).ToArray()");
        string[] output = dinosaurs.GetRange(2, 3).ToArray();

        Console.WriteLine();
        foreach( string dinosaur in output )
        {
            Console.WriteLine(dinosaur);
        }
    }
}

/* This code example produces the following output:

Capacity: 3

Brachiosaurus
Amargasaurus
Mamenchisaurus

AddRange(dinosaurs)

Brachiosaurus
Amargasaurus
Mamenchisaurus
Brachiosaurus
Amargasaurus
Mamenchisaurus

RemoveRange(2, 2)

Brachiosaurus
Amargasaurus
Amargasaurus
Mamenchisaurus

InsertRange(3, input)

Brachiosaurus
Amargasaurus
Amargasaurus
Tyrannosaurus
Deinonychus
Velociraptor
Mamenchisaurus

output = dinosaurs.GetRange(2, 3).ToArray()

Amargasaurus
Tyrannosaurus
Deinonychus
 */
Imports System.Collections.Generic

Public Class Example

    Public Shared Sub Main()

        Dim input() As String = { "Brachiosaurus", _
                                  "Amargasaurus", _
                                  "Mamenchisaurus" }

        Dim dinosaurs As New List(Of String)(input)

        Console.WriteLine(vbLf & "Capacity: {0}", dinosaurs.Capacity)

        Console.WriteLine()
        For Each dinosaur As String In dinosaurs
            Console.WriteLine(dinosaur)
        Next

        Console.WriteLine(vbLf & "AddRange(dinosaurs)")
        dinosaurs.AddRange(dinosaurs)

        Console.WriteLine()
        For Each dinosaur As String In dinosaurs
            Console.WriteLine(dinosaur)
        Next

        Console.WriteLine(vbLf & "RemoveRange(2, 2)")
        dinosaurs.RemoveRange(2, 2)

        Console.WriteLine()
        For Each dinosaur As String In dinosaurs
            Console.WriteLine(dinosaur)
        Next

        input = New String() { "Tyrannosaurus", _
                               "Deinonychus", _
                               "Velociraptor" }

        Console.WriteLine(vbLf & "InsertRange(3, input)")
        dinosaurs.InsertRange(3, input)

        Console.WriteLine()
        For Each dinosaur As String In dinosaurs
            Console.WriteLine(dinosaur)
        Next

        Console.WriteLine(vbLf & "output = dinosaurs.GetRange(2, 3).ToArray")
        Dim output() As String = dinosaurs.GetRange(2, 3).ToArray()
        
        Console.WriteLine()
        For Each dinosaur As String In output
            Console.WriteLine(dinosaur)
        Next

    End Sub
End Class

' This code example produces the following output:
'
'Capacity: 3
'
'Brachiosaurus
'Amargasaurus
'Mamenchisaurus
'
'AddRange(dinosaurs)
'
'Brachiosaurus
'Amargasaurus
'Mamenchisaurus
'Brachiosaurus
'Amargasaurus
'Mamenchisaurus
'
'RemoveRange(2, 2)
'
'Brachiosaurus
'Amargasaurus
'Amargasaurus
'Mamenchisaurus
'
'InsertRange(3, input)
'
'Brachiosaurus
'Amargasaurus
'Amargasaurus
'Tyrannosaurus
'Deinonychus
'Velociraptor
'Mamenchisaurus
'
'output = dinosaurs.GetRange(2, 3).ToArray
'
'Amargasaurus
'Tyrannosaurus
'Deinonychus

Comentarios

Los elementos se copian List<T> en en el mismo orden en que los lee el enumerador de la colección.The elements are copied onto the List<T> in the same order they are read by the enumerator of the collection.

Este constructor es una operación O (n), donde n es el número de elementos de collection .This constructor is an O(n) operation, where n is the number of elements in collection.

Consulte también

Se aplica a

List<T>(Int32)

Inicializa una nueva instancia de la clase List<T> que está vacía y tiene la capacidad inicial especificada.Initializes a new instance of the List<T> class that is empty and has the specified initial capacity.

public:
 List(int capacity);
public List (int capacity);
new System.Collections.Generic.List<'T> : int -> System.Collections.Generic.List<'T>
Public Sub New (capacity As Integer)

Parámetros

capacity
Int32

Número de elementos que puede almacenar inicialmente la lista nueva.The number of elements that the new list can initially store.

Excepciones

capacity es menor que 0.capacity is less than 0.

Ejemplos

En el siguiente ejemplo se muestra el List<T>(Int32) constructor.The following example demonstrates the List<T>(Int32) constructor. List<T>Se crea un de cadenas con una capacidad de 4, ya que se sabe que el tamaño final de la lista es exactamente 4.A List<T> of strings with a capacity of 4 is created, because the ultimate size of the list is known to be exactly 4. La lista se rellena con cuatro cadenas y se crea una copia de solo lectura mediante el AsReadOnly método.The list is populated with four strings, and a read-only copy is created by using the AsReadOnly method.

using namespace System;
using namespace System::Collections::Generic;

void main()
{
    List<String^>^ dinosaurs = gcnew List<String^>(4);

    Console::WriteLine("\nCapacity: {0}", dinosaurs->Capacity);

    dinosaurs->Add("Tyrannosaurus");
    dinosaurs->Add("Amargasaurus");
    dinosaurs->Add("Mamenchisaurus");
    dinosaurs->Add("Deinonychus");

    Console::WriteLine();
    for each(String^ dinosaur in dinosaurs)
    {
        Console::WriteLine(dinosaur);
    }

    Console::WriteLine("\nIList<String^>^ roDinosaurs = dinosaurs->AsReadOnly()");
    IList<String^>^ roDinosaurs = dinosaurs->AsReadOnly();

    Console::WriteLine("\nElements in the read-only IList:");
    for each(String^ dinosaur in roDinosaurs)
    {
        Console::WriteLine(dinosaur);
    }

    Console::WriteLine("\ndinosaurs[2] = \"Coelophysis\"");
    dinosaurs[2] = "Coelophysis";

    Console::WriteLine("\nElements in the read-only IList:");
    for each(String^ dinosaur in roDinosaurs)
    {
        Console::WriteLine(dinosaur);
    }
}

/* This code example produces the following output:

Capacity: 4

Tyrannosaurus
Amargasaurus
Mamenchisaurus
Deinonychus

IList<String^>^ roDinosaurs = dinosaurs->AsReadOnly()

Elements in the read-only IList:
Tyrannosaurus
Amargasaurus
Mamenchisaurus
Deinonychus

dinosaurs[2] = "Coelophysis"

Elements in the read-only IList:
Tyrannosaurus
Amargasaurus
Coelophysis
Deinonychus
 */
using System;
using System.Collections.Generic;

public class Example
{
    public static void Main()
    {
        List<string> dinosaurs = new List<string>(4);

        Console.WriteLine("\nCapacity: {0}", dinosaurs.Capacity);

        dinosaurs.Add("Tyrannosaurus");
        dinosaurs.Add("Amargasaurus");
        dinosaurs.Add("Mamenchisaurus");
        dinosaurs.Add("Deinonychus");

        Console.WriteLine();
        foreach(string s in dinosaurs)
        {
            Console.WriteLine(s);
        }

        Console.WriteLine("\nIList<string> roDinosaurs = dinosaurs.AsReadOnly()");
        IList<string> roDinosaurs = dinosaurs.AsReadOnly();

        Console.WriteLine("\nElements in the read-only IList:");
        foreach(string dinosaur in roDinosaurs)
        {
            Console.WriteLine(dinosaur);
        }

        Console.WriteLine("\ndinosaurs[2] = \"Coelophysis\"");
        dinosaurs[2] = "Coelophysis";

        Console.WriteLine("\nElements in the read-only IList:");
        foreach(string dinosaur in roDinosaurs)
        {
            Console.WriteLine(dinosaur);
        }
    }
}

/* This code example produces the following output:

Capacity: 4

Tyrannosaurus
Amargasaurus
Mamenchisaurus
Deinonychus

IList<string> roDinosaurs = dinosaurs.AsReadOnly()

Elements in the read-only IList:
Tyrannosaurus
Amargasaurus
Mamenchisaurus
Deinonychus

dinosaurs[2] = "Coelophysis"

Elements in the read-only IList:
Tyrannosaurus
Amargasaurus
Coelophysis
Deinonychus
 */
Imports System.Collections.Generic

Public Class Example

    Public Shared Sub Main()

        Dim dinosaurs As New List(Of String)(4)

        Console.WriteLine(vbLf & "Capacity: {0}", dinosaurs.Capacity)

        dinosaurs.Add("Tyrannosaurus")
        dinosaurs.Add("Amargasaurus")
        dinosaurs.Add("Mamenchisaurus")
        dinosaurs.Add("Deinonychus")

        Console.WriteLine()
        For Each dinosaur As String In dinosaurs
            Console.WriteLine(dinosaur)
        Next

        Console.WriteLine(vbLf & _
            "Dim roDinosaurs As IList(Of String) = dinosaurs.AsReadOnly")
        Dim roDinosaurs As IList(Of String) = dinosaurs.AsReadOnly

        Console.WriteLine(vbLf & "Elements in the read-only IList:")
        For Each dinosaur As String In roDinosaurs
            Console.WriteLine(dinosaur)
        Next

        Console.WriteLine(vbLf & "dinosaurs(2) = ""Coelophysis""")
        dinosaurs(2) = "Coelophysis"

        Console.WriteLine(vbLf & "Elements in the read-only IList:")
        For Each dinosaur As String In roDinosaurs
            Console.WriteLine(dinosaur)
        Next

    End Sub
End Class

' This code example produces the following output:
'
'Capacity: 4
'
'Tyrannosaurus
'Amargasaurus
'Mamenchisaurus
'Deinonychus
'
'Dim roDinosaurs As IList(Of String) = dinosaurs.AsReadOnly
'
'Elements in the read-only IList:
'Tyrannosaurus
'Amargasaurus
'Mamenchisaurus
'Deinonychus
'
'dinosaurs(2) = "Coelophysis"
'
'Elements in the read-only IList:
'Tyrannosaurus
'Amargasaurus
'Coelophysis
'Deinonychus

Comentarios

La capacidad de List<T> es el número de elementos que List<T> puede contener.The capacity of a List<T> is the number of elements that the List<T> can hold. A medida que se agregan elementos a una List<T> , la capacidad aumenta automáticamente según sea necesario reasignando la matriz interna.As elements are added to a List<T>, the capacity is automatically increased as required by reallocating the internal array.

Si se puede calcular el tamaño de la colección, al especificar la capacidad inicial, se elimina la necesidad de realizar una serie de operaciones de cambio de tamaño al agregar elementos a List<T> .If the size of the collection can be estimated, specifying the initial capacity eliminates the need to perform a number of resizing operations while adding elements to the List<T>.

La capacidad se puede reducir llamando al TrimExcess método o estableciendo la Capacity propiedad explícitamente.The capacity can be decreased by calling the TrimExcess method or by setting the Capacity property explicitly. Al reducir la capacidad, se reasigna la memoria y se copian todos los elementos de List<T> .Decreasing the capacity reallocates memory and copies all the elements in the List<T>.

Este constructor es una operación O (n), donde n es capacity .This constructor is an O(n) operation, where n is capacity.

Consulte también

Se aplica a