IList Interfaz
Definición
Importante
Parte de la información hace referencia a la versión preliminar del producto, que puede haberse modificado sustancialmente antes de lanzar la versión definitiva. Microsoft no otorga ninguna garantía, explícita o implícita, con respecto a la información proporcionada aquí.
Representa una colección no genérica de objetos a los que el índice puede tener acceso individualmente.
public interface class IList : System::Collections::ICollection
public interface IList : System.Collections.ICollection
[System.Runtime.InteropServices.ComVisible(true)]
public interface IList : System.Collections.ICollection
type IList = interface
interface ICollection
interface IEnumerable
[<System.Runtime.InteropServices.ComVisible(true)>]
type IList = interface
interface ICollection
interface IEnumerable
Public Interface IList
Implements ICollection
- Derivado
- Atributos
- Implementaciones
Ejemplos
En el ejemplo siguiente se muestra la implementación de la interfaz de IList para crear una lista de tamaño fijo simple.
using System;
using System.Collections;
class Program
{
static void Main()
{
var test = new SimpleList();
// Populate the List.
Console.WriteLine("Populate the List");
test.Add("one");
test.Add("two");
test.Add("three");
test.Add("four");
test.Add("five");
test.Add("six");
test.Add("seven");
test.Add("eight");
test.PrintContents();
Console.WriteLine();
// Remove elements from the list.
Console.WriteLine("Remove elements from the list");
test.Remove("six");
test.Remove("eight");
test.PrintContents();
Console.WriteLine();
// Add an element to the end of the list.
Console.WriteLine("Add an element to the end of the list");
test.Add("nine");
test.PrintContents();
Console.WriteLine();
// Insert an element into the middle of the list.
Console.WriteLine("Insert an element into the middle of the list");
test.Insert(4, "number");
test.PrintContents();
Console.WriteLine();
// Check for specific elements in the list.
Console.WriteLine("Check for specific elements in the list");
Console.WriteLine($"List contains \"three\": {test.Contains("three")}");
Console.WriteLine($"List contains \"ten\": {test.Contains("ten")}");
}
}
class SimpleList : IList
{
private object[] _contents = new object[8];
private int _count;
public SimpleList()
{
_count = 0;
}
// IList Members
public int Add(object value)
{
if (_count < _contents.Length)
{
_contents[_count] = value;
_count++;
return (_count - 1);
}
return -1;
}
public void Clear()
{
_count = 0;
}
public bool Contains(object value)
{
for (int i = 0; i < Count; i++)
{
if (_contents[i] == value)
{
return true;
}
}
return false;
}
public int IndexOf(object value)
{
for (int i = 0; i < Count; i++)
{
if (_contents[i] == value)
{
return i;
}
}
return -1;
}
public void Insert(int index, object value)
{
if ((_count + 1 <= _contents.Length) && (index < Count) && (index >= 0))
{
_count++;
for (int i = Count - 1; i > index; i--)
{
_contents[i] = _contents[i - 1];
}
_contents[index] = value;
}
}
public bool IsFixedSize
{
get
{
return true;
}
}
public bool IsReadOnly
{
get
{
return false;
}
}
public void Remove(object value)
{
RemoveAt(IndexOf(value));
}
public void RemoveAt(int index)
{
if ((index >= 0) && (index < Count))
{
for (int i = index; i < Count - 1; i++)
{
_contents[i] = _contents[i + 1];
}
_count--;
}
}
public object this[int index]
{
get
{
return _contents[index];
}
set
{
_contents[index] = value;
}
}
// ICollection members.
public void CopyTo(Array array, int index)
{
for (int i = 0; i < Count; i++)
{
array.SetValue(_contents[i], index++);
}
}
public int Count
{
get
{
return _count;
}
}
public bool IsSynchronized
{
get
{
return false;
}
}
// Return the current instance since the underlying store is not
// publicly available.
public object SyncRoot
{
get
{
return this;
}
}
// IEnumerable Members
public IEnumerator GetEnumerator()
{
// Refer to the IEnumerator documentation for an example of
// implementing an enumerator.
throw new NotImplementedException("The method or operation is not implemented.");
}
public void PrintContents()
{
Console.WriteLine($"List has a capacity of {_contents.Length} and currently has {_count} elements.");
Console.Write("List contents:");
for (int i = 0; i < Count; i++)
{
Console.Write($" {_contents[i]}");
}
Console.WriteLine();
}
}
// This code produces output similar to the following:
// Populate the List:
// List has a capacity of 8 and currently has 8 elements.
// List contents: one two three four five six seven eight
//
// Remove elements from the list:
// List has a capacity of 8 and currently has 6 elements.
// List contents: one two three four five seven
//
// Add an element to the end of the list:
// List has a capacity of 8 and currently has 7 elements.
// List contents: one two three four five seven nine
//
// Insert an element into the middle of the list:
// List has a capacity of 8 and currently has 8 elements.
// List contents: one two three four number five seven nine
//
// Check for specific elements in the list:
// List contains "three": True
// List contains "ten": False
Imports System.Collections
Public Class Program
Shared Sub Main()
Dim myList As New SimpleList()
' Populate the List.
Console.WriteLine("Populate the List")
myList.Add("one")
myList.Add("two")
myList.Add("three")
myList.Add("four")
myList.Add("five")
myList.Add("six")
myList.Add("seven")
myList.Add("eight")
myList.PrintContents()
Console.WriteLine()
' Remove elements from the list.
Console.WriteLine("Remove elements from the list")
myList.Remove("six")
myList.Remove("eight")
myList.PrintContents()
Console.WriteLine()
' Add an element to the end of the list.
Console.WriteLine("Add an element to the end of the list")
myList.Add("nine")
myList.PrintContents()
Console.WriteLine()
' Insert an element into the middle of the list.
Console.WriteLine("Insert an element into the middle of the list")
myList.Insert(4, "number")
myList.PrintContents()
Console.WriteLine()
' Check for specific elements in the list.
Console.WriteLine("Check for specific elements in the list")
Console.WriteLine($"List contains 'three': {myList.Contains("three")}")
Console.WriteLine($"List contains 'ten': {myList.Contains("ten")}")
End Sub
End Class
Public Class SimpleList
Implements IList
Private _contents(7) As Object
Private _count As Integer
Public Sub New()
_count = 0
End Sub
' IList members.
Public Function Add(ByVal value As Object) As Integer Implements IList.Add
If _count < _contents.Length Then
_contents(_count) = value
_count += 1
Return _count - 1
End If
Return -1
End Function
Public Sub Clear() Implements IList.Clear
_count = 0
End Sub
Public Function Contains(ByVal value As Object) As Boolean Implements IList.Contains
For i As Integer = 0 To Count - 1
If _contents(i) = value Then Return True
Next
Return False
End Function
Public Function IndexOf(ByVal value As Object) As Integer Implements IList.IndexOf
For i As Integer = 0 To Count - 1
If _contents(i) = value Then Return i
Next
Return -1
End Function
Public Sub Insert(ByVal index As Integer, ByVal value As Object) Implements IList.Insert
If _count + 1 <= _contents.Length AndAlso index < Count AndAlso index >= 0 Then
_count += 1
For i As Integer = Count - 1 To index Step -1
_contents(i) = _contents(i - 1)
Next
_contents(index) = value
End If
End Sub
Public ReadOnly Property IsFixedSize() As Boolean Implements IList.IsFixedSize
Get
Return True
End Get
End Property
Public ReadOnly Property IsReadOnly() As Boolean Implements IList.IsReadOnly
Get
Return False
End Get
End Property
Public Sub Remove(ByVal value As Object) Implements IList.Remove
RemoveAt(IndexOf(value))
End Sub
Public Sub RemoveAt(ByVal index As Integer) Implements IList.RemoveAt
if index >= 0 AndAlso index < Count Then
for i As Integer = index To Count - 2
_contents(i) = _contents(i + 1)
Next
_count -= 1
End If
End Sub
Public Property Item(ByVal index As Integer) As Object Implements IList.Item
Get
Return _contents(index)
End Get
Set(ByVal value As Object)
_contents(index) = value
End Set
End Property
' ICollection members.
Public Sub CopyTo(ByVal array As Array, ByVal index As Integer) Implements ICollection.CopyTo
For i As Integer = 0 To Count - 1
array.SetValue(_contents(i), index)
index += 1
Next
End Sub
Public ReadOnly Property Count() As Integer Implements ICollection.Count
Get
Return _count
End Get
End Property
Public ReadOnly Property IsSynchronized() As Boolean Implements ICollection.IsSynchronized
Get
Return False
End Get
End Property
' Return the current instance since the underlying store is not
' publicly available.
Public ReadOnly Property SyncRoot() As Object Implements ICollection.SyncRoot
Get
Return Me
End Get
End Property
' IEnumerable members.
Public Function GetEnumerator() As IEnumerator Implements IEnumerable.GetEnumerator
' Refer to the IEnumerator documentation for an example of
' implementing an enumerator.
Throw New NotImplementedException("The method or operation is not implemented.")
End Function
Public Sub PrintContents()
Console.WriteLine($"List has a capacity of {_contents.Length} and currently has {_count} elements.")
Console.Write("List contents:")
For i As Integer = 0 To Count - 1
Console.Write($" {_contents(i)}")
Next
Console.WriteLine()
End Sub
End Class
' This code produces output similar to the following:
' Populate the List:
' List has a capacity of 8 and currently has 8 elements.
' List contents: one two three four five six seven eight
'
' Remove elements from the list:
' List has a capacity of 8 and currently has 6 elements.
' List contents: one two three four five seven
'
' Add an element to the end of the list:
' List has a capacity of 8 and currently has 7 elements.
' List contents: one two three four five seven nine
'
' Insert an element into the middle of the list:
' List has a capacity of 8 and currently has 8 elements.
' List contents: one two three four number five seven nine
'
' Check for specific elements in the list:
' List contains "three": True
' List contains "ten": False
Comentarios
IList es un descendiente de la interfaz ICollection y es la interfaz base de todas las listas no genéricas. IList implementaciones se dividen en tres categorías: solo lectura, tamaño fijo y tamaño variable. No se puede modificar un IList de solo lectura. Una IList de tamaño fijo no permite la adición o eliminación de elementos, pero permite la modificación de los elementos existentes. Un IList de tamaño variable permite la adición, eliminación y modificación de elementos.
Para obtener la versión genérica de esta interfaz, consulte System.Collections.Generic.IList<T>.
Propiedades
Count |
Obtiene el número de elementos contenidos en el ICollection. (Heredado de ICollection) |
IsFixedSize |
Obtiene un valor que indica si el IList tiene un tamaño fijo. |
IsReadOnly |
Obtiene un valor que indica si el IList es de solo lectura. |
IsSynchronized |
Obtiene un valor que indica si el acceso a la ICollection está sincronizado (seguro para subprocesos). (Heredado de ICollection) |
Item[Int32] |
Obtiene o establece el elemento en el índice especificado. |
SyncRoot |
Obtiene un objeto que se puede usar para sincronizar el acceso a la ICollection. (Heredado de ICollection) |
Métodos
Add(Object) |
Agrega un elemento al IList. |
Clear() |
Quita todos los elementos de la IList. |
Contains(Object) |
Determina si el IList contiene un valor específico. |
CopyTo(Array, Int32) |
Copia los elementos del ICollection en un Array, empezando por un índice de Array determinado. (Heredado de ICollection) |
GetEnumerator() |
Devuelve un enumerador que recorre en iteración una colección. (Heredado de IEnumerable) |
IndexOf(Object) |
Determina el índice de un elemento específico del IList. |
Insert(Int32, Object) |
Inserta un elemento en el IList en el índice especificado. |
Remove(Object) |
Quita la primera aparición de un objeto específico de la IList. |
RemoveAt(Int32) |
Quita el elemento IList en el índice especificado. |
Métodos de extensión
Cast<TResult>(IEnumerable) |
Convierte los elementos de un IEnumerable al tipo especificado. |
OfType<TResult>(IEnumerable) |
Filtra los elementos de un IEnumerable en función de un tipo especificado. |
AsParallel(IEnumerable) |
Habilita la paralelización de una consulta. |
AsQueryable(IEnumerable) |
Convierte un IEnumerable en un IQueryable. |