แก้ไข

แชร์ผ่าน


ArrayList.Repeat(Object, Int32) Method

Definition

Returns an ArrayList whose elements are copies of the specified value.

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

Parameters

value
Object

The Object to copy multiple times in the new ArrayList. The value can be null.

count
Int32

The number of times value should be copied.

Returns

An ArrayList with count number of elements, all of which are copies of value.

Exceptions

count is less than zero.

Examples

The following code example shows how to create and initialize a new ArrayList with the same value.

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

Remarks

ArrayList accepts null as a valid value and allows duplicate elements.

This method is an O(n) operation, where n is count.

Applies to