ArrayList.GetRange(Int32, Int32) Metodo
Definizione
Importante
Alcune informazioni sono relative alla release non definitiva del prodotto, che potrebbe subire modifiche significative prima della release definitiva. Microsoft non riconosce alcuna garanzia, espressa o implicita, in merito alle informazioni qui fornite.
public:
virtual System::Collections::ArrayList ^ GetRange(int index, int count);
public virtual System.Collections.ArrayList GetRange (int index, int count);
abstract member GetRange : int * int -> System.Collections.ArrayList
override this.GetRange : int * int -> System.Collections.ArrayList
Public Overridable Function GetRange (index As Integer, count As Integer) As ArrayList
Parametri
- count
- Int32
Numero di elementi nell'intervallo.
Restituisce
Oggetto ArrayList che rappresenta un subset di elementi nell'oggetto ArrayList di origine.
Eccezioni
index
e count
non indicano un intervallo valido di elementi nell'oggetto ArrayList.
Esempio
Nell'esempio di codice seguente viene illustrato come impostare e ottenere un intervallo di elementi in ArrayList.
using namespace System;
using namespace System::Collections;
void PrintValues( IEnumerable^ myList, char mySeparator );
int main()
{
// Creates and initializes a new ArrayList.
ArrayList^ myAL = gcnew ArrayList;
myAL->Add( "The" );
myAL->Add( "quick" );
myAL->Add( "brown" );
myAL->Add( "fox" );
myAL->Add( "jumps" );
myAL->Add( "over" );
myAL->Add( "the" );
myAL->Add( "lazy" );
myAL->Add( "dog" );
// Creates and initializes the source ICollection.
Queue^ mySourceList = gcnew Queue;
mySourceList->Enqueue( "big" );
mySourceList->Enqueue( "gray" );
mySourceList->Enqueue( "wolf" );
// Displays the values of five elements starting at index 0.
ArrayList^ mySubAL = myAL->GetRange( 0, 5 );
Console::WriteLine( "Index 0 through 4 contains:" );
PrintValues( mySubAL, '\t' );
// Replaces the values of five elements starting at index 1 with the values in the ICollection.
myAL->SetRange( 1, mySourceList );
// Displays the values of five elements starting at index 0.
mySubAL = myAL->GetRange( 0, 5 );
Console::WriteLine( "Index 0 through 4 now contains:" );
PrintValues( mySubAL, '\t' );
}
void PrintValues( IEnumerable^ myList, char mySeparator )
{
IEnumerator^ myEnum = myList->GetEnumerator();
while ( myEnum->MoveNext() )
{
Object^ obj = safe_cast<Object^>(myEnum->Current);
Console::Write( "{0}{1}", mySeparator, obj );
}
Console::WriteLine();
}
/*
This code produces the following output.
Index 0 through 4 contains:
The quick brown fox jumps
Index 0 through 4 now contains:
The big gray wolf jumps
*/
using System;
using System.Collections;
public class SamplesArrayList {
public static void Main() {
// Creates and initializes a new ArrayList.
ArrayList myAL = new ArrayList();
myAL.Add( "The" );
myAL.Add( "quick" );
myAL.Add( "brown" );
myAL.Add( "fox" );
myAL.Add( "jumps" );
myAL.Add( "over" );
myAL.Add( "the" );
myAL.Add( "lazy" );
myAL.Add( "dog" );
// Creates and initializes the source ICollection.
Queue mySourceList = new Queue();
mySourceList.Enqueue( "big" );
mySourceList.Enqueue( "gray" );
mySourceList.Enqueue( "wolf" );
// Displays the values of five elements starting at index 0.
ArrayList mySubAL = myAL.GetRange( 0, 5 );
Console.WriteLine( "Index 0 through 4 contains:" );
PrintValues( mySubAL, '\t' );
// Replaces the values of five elements starting at index 1 with the values in the ICollection.
myAL.SetRange( 1, mySourceList );
// Displays the values of five elements starting at index 0.
mySubAL = myAL.GetRange( 0, 5 );
Console.WriteLine( "Index 0 through 4 now contains:" );
PrintValues( mySubAL, '\t' );
}
public static void PrintValues( IEnumerable myList, char mySeparator ) {
foreach ( Object obj in myList )
Console.Write( "{0}{1}", mySeparator, obj );
Console.WriteLine();
}
}
/*
This code produces the following output.
Index 0 through 4 contains:
The quick brown fox jumps
Index 0 through 4 now contains:
The big gray wolf jumps
*/
Imports System.Collections
Public Class SamplesArrayList
Public Shared Sub Main()
' Creates and initializes a new ArrayList.
Dim myAL As New ArrayList()
myAL.Add("The")
myAL.Add("quick")
myAL.Add("brown")
myAL.Add("fox")
myAL.Add("jumps")
myAL.Add("over")
myAL.Add("the")
myAL.Add("lazy")
myAL.Add("dog")
' Creates and initializes the source ICollection.
Dim mySourceList As New Queue()
mySourceList.Enqueue("big")
mySourceList.Enqueue("gray")
mySourceList.Enqueue("wolf")
' Displays the values of five elements starting at index 0.
Dim mySubAL As ArrayList = myAL.GetRange(0, 5)
Console.WriteLine("Index 0 through 4 contains:")
PrintValues(mySubAL, vbTab)
' Replaces the values of five elements starting at index 1 with the values in the ICollection.
myAL.SetRange(1, mySourceList)
' Displays the values of five elements starting at index 0.
mySubAL = myAL.GetRange(0, 5)
Console.WriteLine("Index 0 through 4 now contains:")
PrintValues(mySubAL, vbTab)
End Sub
Public Shared Sub PrintValues(myList As IEnumerable, mySeparator As Char)
Dim obj As [Object]
For Each obj In myList
Console.Write("{0}{1}", mySeparator, obj)
Next obj
Console.WriteLine()
End Sub
End Class
' This code produces the following output.
'
' Index 0 through 4 contains:
' The quick brown fox jumps
' Index 0 through 4 now contains:
' The big gray wolf jumps
Commenti
Questo metodo non crea copie degli elementi. Il nuovo ArrayList oggetto è solo una finestra di visualizzazione nell'origine ArrayList. Tuttavia, tutte le modifiche successive all'origine ArrayList devono essere eseguite tramite questa finestra di ArrayListvisualizzazione. Se le modifiche vengono apportate direttamente all'origine ArrayList, la finestra ArrayList di visualizzazione viene invalidata e qualsiasi operazione su di essa restituirà un oggetto InvalidOperationException.
Questo metodo è un'operazione O(1)
.