ArrayList.Reverse Method ()

 

Reverses the order of the elements in the entire ArrayList.

Namespace:   System.Collections
Assembly:  mscorlib (in mscorlib.dll)

public virtual void Reverse()

Exception Condition
NotSupportedException

The ArrayList is read-only.

This method uses Array.Reverse to reverse the order of the elements, such that the element at ArrayList [i], where i is any index within the range, moves to ArrayList [j], where j equals index + index + count - i - 1.

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

The following code example shows how to reverse the sort order of the values in an ArrayList.

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" );

      // Displays the values of the ArrayList.
      Console.WriteLine( "The ArrayList initially contains the following values:" );
      PrintValues( myAL );

      // Reverses the sort order of the values of the ArrayList.
      myAL.Reverse();

      // Displays the values of the ArrayList.
      Console.WriteLine( "After reversing:" );
      PrintValues( myAL );
   }

   public static void PrintValues( IEnumerable myList )  {
      foreach ( Object obj in myList )
         Console.WriteLine( "   {0}", obj );
      Console.WriteLine();
   }

}


/* 
This code produces the following output.

The ArrayList initially contains the following values:
   The
   quick
   brown
   fox
   jumps
   over
   the
   lazy
   dog

After reversing:
   dog
   lazy
   the
   over
   jumps
   fox
   brown
   quick
   The
*/ 

Universal Windows Platform
Available since 10
.NET Framework
Available since 1.1
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