ArrayList.Repeat(Object, Int32) Metodo

Definizione

Spazio dei nomi:

System.Collections

Assembly:

System.Runtime.dll

Source:

ArrayList.cs

Restituisce un ArrayList i cui elementi sono copie del valore specificato.

public:
 static System::Collections::ArrayList ^ Repeat(System::Object ^ value, int count);

public static System.Collections.ArrayList Repeat (object? value, int count);

static member Repeat : obj * int -> System.Collections.ArrayList

Public Shared Function Repeat (value As Object, count As Integer) As ArrayList

Parametri

value

Object

Oggetto Object da copiare più volte nel nuovo ArrayList. Il valore può essere null.

count

Int32

Numero di volte che value deve essere copiato.

Restituisce

ArrayList

ArrayList con un numero di elementi pari a count, dei quali tutti sono copie di value.

Eccezioni

ArgumentOutOfRangeException

count è minore di zero.

Esempio

Nell'esempio di codice seguente viene illustrato come creare e inizializzare un nuovo ArrayList con lo stesso valore.

using namespace System;
using namespace System::Collections;
void PrintValues( IEnumerable^ myList );
int main()
{
   
   // Creates a new ArrayList with five elements and initialize each element with a null value.
   ArrayList^ myAL = ArrayList::Repeat( 0, 5 );
   
   // Displays the count, capacity and values of the ArrayList.
   Console::WriteLine( "ArrayList with five elements with a null value" );
   Console::WriteLine( "   Count    : {0}", myAL->Count );
   Console::WriteLine( "   Capacity : {0}", myAL->Capacity );
   Console::Write( "   Values:" );
   PrintValues( myAL );
   
   // Creates a new ArrayList with seven elements and initialize each element with the string "abc".
   myAL = ArrayList::Repeat( "abc", 7 );
   
   // Displays the count, capacity and values of the ArrayList.
   Console::WriteLine( "ArrayList with seven elements with a string value" );
   Console::WriteLine( "   Count    : {0}", myAL->Count );
   Console::WriteLine( "   Capacity : {0}", myAL->Capacity );
   Console::Write( "   Values:" );
   PrintValues( myAL );
}

void PrintValues( IEnumerable^ myList )
{
   IEnumerator^ myEnum = myList->GetEnumerator();
   while ( myEnum->MoveNext() )
   {
      Object^ obj = safe_cast<Object^>(myEnum->Current);
      Console::Write( "   {0}", obj );
   }

   Console::WriteLine();
}

/* 
 This code produces the following output.
 
 ArrayList with five elements with a null value
    Count    : 5
    Capacity : 16
    Values:
 ArrayList with seven elements with a string value
    Count    : 7
    Capacity : 16
    Values:   abc   abc   abc   abc   abc   abc   abc

 */

using System;
using System.Collections;
public class SamplesArrayList  {

   public static void Main()  {

      // Creates a new ArrayList with five elements and initialize each element with a null value.
      ArrayList myAL = ArrayList.Repeat( null, 5 );

      // Displays the count, capacity and values of the ArrayList.
      Console.WriteLine( "ArrayList with five elements with a null value" );
      Console.WriteLine( "   Count    : {0}", myAL.Count );
      Console.WriteLine( "   Capacity : {0}", myAL.Capacity );
      Console.Write( "   Values:" );
      PrintValues( myAL );

      // Creates a new ArrayList with seven elements and initialize each element with the string "abc".
      myAL = ArrayList.Repeat( "abc", 7 );

      // Displays the count, capacity and values of the ArrayList.
      Console.WriteLine( "ArrayList with seven elements with a string value" );
      Console.WriteLine( "   Count    : {0}", myAL.Count );
      Console.WriteLine( "   Capacity : {0}", myAL.Capacity );
      Console.Write( "   Values:" );
      PrintValues( myAL );
   }

   public static void PrintValues( IEnumerable myList )  {
      foreach ( Object obj in myList )
         Console.Write( "   {0}", obj );
      Console.WriteLine();
   }
}
/*
This code produces the following output.

ArrayList with five elements with a null value
   Count    : 5
   Capacity : 16
   Values:
ArrayList with seven elements with a string value
   Count    : 7
   Capacity : 16
   Values:   abc   abc   abc   abc   abc   abc   abc

*/

Imports System.Collections

Public Class SamplesArrayList    

    Public Shared Sub Main()

        ' Creates a new ArrayList with five elements and initialize each
        ' element with a null value.
        Dim myAL As ArrayList = ArrayList.Repeat(Nothing, 5)

        ' Displays the count, capacity and values of the ArrayList.
        Console.WriteLine("ArrayList with five elements with a null value")
        Console.WriteLine("   Count    : {0}", myAL.Count)
        Console.WriteLine("   Capacity : {0}", myAL.Capacity)
        Console.Write("   Values:")
        PrintValues(myAL)

        ' Creates a new ArrayList with seven elements and initialize each
        ' element with the string "abc".
        myAL = ArrayList.Repeat("abc", 7)

        ' Displays the count, capacity and values of the ArrayList.
        Console.WriteLine("ArrayList with seven elements with a string value")
        Console.WriteLine("   Count    : {0}", myAL.Count)
        Console.WriteLine("   Capacity : {0}", myAL.Capacity)
        Console.Write("   Values:")
        PrintValues(myAL)

    End Sub

    Public Shared Sub PrintValues(myList As IEnumerable)
        Dim obj As [Object]
        For Each obj In  myList
            Console.Write("   {0}", obj)
        Next obj
        Console.WriteLine()
    End Sub

End Class


' This code produces the following output.
' 
' ArrayList with five elements with a null value
'    Count    : 5
'    Capacity : 16
'    Values:					
' ArrayList with seven elements with a string value
'    Count    : 7
'    Capacity : 16
'    Values:	abc	abc	abc	abc	abc	abc	abc

Commenti

ArrayList accetta null come valore valido e consente elementi duplicati.

Questo metodo è un'operazione O(n) , dove n è count.