IList Interfaz
Definición
Representa una colección no genérica de objetos a los que se puede acceder individualmente por un índice.Represents a non-generic collection of objects that can be individually accessed by index.
public interface class IList : System::Collections::ICollectionpublic interface IList : System.Collections.ICollection[System.Runtime.InteropServices.ComVisible(true)]
public interface IList : System.Collections.ICollectiontype IList = interface
interface ICollection
interface IEnumerable[<System.Runtime.InteropServices.ComVisible(true)>]
type IList = interface
interface ICollection
interface IEnumerablePublic Interface IList
Implements ICollection- Derivado
- Atributos
- Implementaciones
Ejemplos
En el ejemplo siguiente se muestra la implementación de la IList interfaz para crear una lista sencilla de tamaño fijo.The following example demonstrates the implementation of the IList interface to create a simple, fixed-size list.
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 ICollection interfaz y es la interfaz base de todas las listas no genéricas.IList is a descendant of the ICollection interface and is the base interface of all non-generic lists. IList las implementaciones se dividen en tres categorías: de solo lectura, de tamaño fijo y de tamaño variable.IList implementations fall into three categories: read-only, fixed-size, and variable-size. No se puede modificar un solo lectura IList .A read-only IList cannot be modified. Un tamaño fijo IList no permite la adición o eliminación de elementos, pero permite la modificación de los elementos existentes.A fixed-size IList does not allow the addition or removal of elements, but it allows the modification of existing elements. Un tamaño variable IList permite agregar, quitar y modificar elementos.A variable-size IList allows the addition, removal, and modification of elements.
Para obtener la versión genérica de esta interfaz, vea System.Collections.Generic.IList<T> .For the generic version of this interface, see System.Collections.Generic.IList<T>.
Propiedades
| Count |
Obtiene el número de elementos incluidos en ICollection.Gets the number of elements contained in the ICollection. (Heredado de ICollection) |
| IsFixedSize |
Obtiene un valor que indica si la interfaz IList tiene un tamaño fijo.Gets a value indicating whether the IList has a fixed size. |
| IsReadOnly |
Obtiene un valor que indica si IList es de solo lectura.Gets a value indicating whether the IList is read-only. |
| IsSynchronized |
Obtiene un valor que indica si el acceso a la interfaz ICollection está sincronizado (es seguro para subprocesos).Gets a value indicating whether access to the ICollection is synchronized (thread safe). (Heredado de ICollection) |
| Item[Int32] |
Obtiene o establece el elemento en el índice especificado.Gets or sets the element at the specified index. |
| SyncRoot |
Obtiene un objeto que se puede usar para sincronizar el acceso a ICollection.Gets an object that can be used to synchronize access to the ICollection. (Heredado de ICollection) |
Métodos
| Add(Object) | |
| Clear() |
Quita todos los elementos de IList.Removes all items from the IList. |
| Contains(Object) |
Determina si IList contiene un valor específico.Determines whether the IList contains a specific value. |
| CopyTo(Array, Int32) |
Copia los elementos de ICollection en Array, empezando por un índice determinado de Array.Copies the elements of the ICollection to an Array, starting at a particular Array index. (Heredado de ICollection) |
| GetEnumerator() |
Devuelve un enumerador que recorre en iteración una colección.Returns an enumerator that iterates through a collection. (Heredado de IEnumerable) |
| IndexOf(Object) |
Determina el índice de un elemento específico de IList.Determines the index of a specific item in the IList. |
| Insert(Int32, Object) |
Inserta un elemento en la interfaz IList, en el índice especificado.Inserts an item to the IList at the specified index. |
| Remove(Object) |
Quita la primera aparición de un objeto específico de la interfaz IList.Removes the first occurrence of a specific object from the IList. |
| RemoveAt(Int32) |
Quita el elemento de la interfaz IList que se encuentra en el índice especificado.Removes the IList item at the specified index. |
Métodos de extensión
| Cast<TResult>(IEnumerable) |
Convierte los elementos de IEnumerable en el tipo especificado.Casts the elements of an IEnumerable to the specified type. |
| OfType<TResult>(IEnumerable) |
Filtra los elementos de IEnumerable en función de un tipo especificado.Filters the elements of an IEnumerable based on a specified type. |
| AsParallel(IEnumerable) |
Habilita la paralelización de una consulta.Enables parallelization of a query. |
| AsQueryable(IEnumerable) |
Convierte una interfaz IEnumerable en IQueryable.Converts an IEnumerable to an IQueryable. |