ReadOnlyCollectionBase.InnerList Propiedad
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.
Obtiene la lista de elementos contenidos en la ReadOnlyCollectionBase instancia de .
protected:
property System::Collections::ArrayList ^ InnerList { System::Collections::ArrayList ^ get(); };
protected System.Collections.ArrayList InnerList { get; }
member this.InnerList : System.Collections.ArrayList
Protected ReadOnly Property InnerList As ArrayList
Valor de propiedad
que ArrayList representa la ReadOnlyCollectionBase propia instancia.
Ejemplos
En el ejemplo de código siguiente se implementa la ReadOnlyCollectionBase clase .
using System;
using System.Collections;
public class ROCollection : ReadOnlyCollectionBase {
public ROCollection( IList sourceList ) {
InnerList.AddRange( sourceList );
}
public Object this[ int index ] {
get {
return( InnerList[index] );
}
}
public int IndexOf( Object value ) {
return( InnerList.IndexOf( value ) );
}
public bool Contains( Object value ) {
return( InnerList.Contains( value ) );
}
}
public class SamplesCollectionBase {
public static void Main() {
// Create an ArrayList.
ArrayList myAL = new ArrayList();
myAL.Add( "red" );
myAL.Add( "blue" );
myAL.Add( "yellow" );
myAL.Add( "green" );
myAL.Add( "orange" );
myAL.Add( "purple" );
// Create a new ROCollection that contains the elements in myAL.
ROCollection myCol = new ROCollection( myAL );
// Display the contents of the collection using foreach. This is the preferred method.
Console.WriteLine( "Contents of the collection (using foreach):" );
PrintValues1( myCol );
// Display the contents of the collection using the enumerator.
Console.WriteLine( "Contents of the collection (using enumerator):" );
PrintValues2( myCol );
// Display the contents of the collection using the Count property and the Item property.
Console.WriteLine( "Contents of the collection (using Count and Item):" );
PrintIndexAndValues( myCol );
// Search the collection with Contains and IndexOf.
Console.WriteLine( "Contains yellow: {0}", myCol.Contains( "yellow" ) );
Console.WriteLine( "orange is at index {0}.", myCol.IndexOf( "orange" ) );
Console.WriteLine();
}
// Uses the Count property and the Item property.
public static void PrintIndexAndValues( ROCollection myCol ) {
for ( int i = 0; i < myCol.Count; i++ )
Console.WriteLine( " [{0}]: {1}", i, myCol[i] );
Console.WriteLine();
}
// Uses the foreach statement which hides the complexity of the enumerator.
// NOTE: The foreach statement is the preferred way of enumerating the contents of a collection.
public static void PrintValues1( ROCollection myCol ) {
foreach ( Object obj in myCol )
Console.WriteLine( " {0}", obj );
Console.WriteLine();
}
// Uses the enumerator.
// NOTE: The foreach statement is the preferred way of enumerating the contents of a collection.
public static void PrintValues2( ROCollection myCol ) {
System.Collections.IEnumerator myEnumerator = myCol.GetEnumerator();
while ( myEnumerator.MoveNext() )
Console.WriteLine( " {0}", myEnumerator.Current );
Console.WriteLine();
}
}
/*
This code produces the following output.
Contents of the collection (using foreach):
red
blue
yellow
green
orange
purple
Contents of the collection (using enumerator):
red
blue
yellow
green
orange
purple
Contents of the collection (using Count and Item):
[0]: red
[1]: blue
[2]: yellow
[3]: green
[4]: orange
[5]: purple
Contains yellow: True
orange is at index 4.
*/
Imports System.Collections
Public Class ROCollection
Inherits ReadOnlyCollectionBase
Public Sub New(sourceList As IList)
InnerList.AddRange(sourceList)
End Sub
Default Public ReadOnly Property Item(index As Integer) As [Object]
Get
Return InnerList(index)
End Get
End Property
Public Function IndexOf(value As [Object]) As Integer
Return InnerList.IndexOf(value)
End Function 'IndexOf
Public Function Contains(value As [Object]) As Boolean
Return InnerList.Contains(value)
End Function 'Contains
End Class
Public Class SamplesCollectionBase
Public Shared Sub Main()
' Create an ArrayList.
Dim myAL As New ArrayList()
myAL.Add("red")
myAL.Add("blue")
myAL.Add("yellow")
myAL.Add("green")
myAL.Add("orange")
myAL.Add("purple")
' Create a new ROCollection that contains the elements in myAL.
Dim myCol As New ROCollection(myAL)
' Display the contents of the collection using For Each. This is the preferred method.
Console.WriteLine("Contents of the collection (using For Each):")
PrintValues1(myCol)
' Display the contents of the collection using the enumerator.
Console.WriteLine("Contents of the collection (using enumerator):")
PrintValues2(myCol)
' Display the contents of the collection using the Count property and the Item property.
Console.WriteLine("Contents of the collection (using Count and Item):")
PrintIndexAndValues(myCol)
' Search the collection with Contains and IndexOf.
Console.WriteLine("Contains yellow: {0}", myCol.Contains("yellow"))
Console.WriteLine("orange is at index {0}.", myCol.IndexOf("orange"))
Console.WriteLine()
End Sub
' Uses the Count property and the Item property.
Public Shared Sub PrintIndexAndValues(myCol As ROCollection)
Dim i As Integer
For i = 0 To myCol.Count - 1
Console.WriteLine(" [{0}]: {1}", i, myCol(i))
Next i
Console.WriteLine()
End Sub
' Uses the For Each statement which hides the complexity of the enumerator.
' NOTE: The For Each statement is the preferred way of enumerating the contents of a collection.
Public Shared Sub PrintValues1(myCol As ROCollection)
Dim obj As [Object]
For Each obj In myCol
Console.WriteLine(" {0}", obj)
Next obj
Console.WriteLine()
End Sub
' Uses the enumerator.
' NOTE: The For Each statement is the preferred way of enumerating the contents of a collection.
Public Shared Sub PrintValues2(myCol As ROCollection)
Dim myEnumerator As System.Collections.IEnumerator = myCol.GetEnumerator()
While myEnumerator.MoveNext()
Console.WriteLine(" {0}", myEnumerator.Current)
End While
Console.WriteLine()
End Sub
End Class
'This code produces the following output.
'
'Contents of the collection (using For Each):
' red
' blue
' yellow
' green
' orange
' purple
'
'Contents of the collection (using enumerator):
' red
' blue
' yellow
' green
' orange
' purple
'
'Contents of the collection (using Count and Item):
' [0]: red
' [1]: blue
' [2]: yellow
' [3]: green
' [4]: orange
' [5]: purple
'
'Contains yellow: True
'orange is at index 4.
Comentarios
Recuperar el valor de esta propiedad es una O(1) operación.
Notas a los desarrolladores de herederos
Esta clase hace que la colección subyacente esté disponible a través de la InnerList propiedad , que está pensada para su uso solo por clases derivadas directamente de ReadOnlyCollectionBase. La clase derivada debe asegurarse de que sus propios usuarios no puedan modificar la colección subyacente.