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Reverse  
Method  		 Reverse the sequence of elements in the ArrayList
ArrayList Class
System.Collections NameSpace
CF1.  Procedure Reverse ( ) ;
CF2.  Procedure Reverse ( StartIndex:IntegerStartIndex : Integer; Count : Integer; ) ;
CF : Methods with this mark are Compact Framework Compatible
Description
The Reverse method reverses the sequence of the elements in the ArrayList. All elements are reversed unless a range is specified via the StartIndex and Count parameters.
Microsoft MSDN Links
System.Collections
System.Collections.ArrayList
 
  
Reversing all elements in an array
program Project1;
{$APPTYPE CONSOLE}

uses
  System.Collections;

var
  List : System.Collections.ArrayList;
  i    : Integer;

begin
  // Create our array list object
  List := ArrayList.Create;

  // Fill it
  List.Add('0.');
  List.Add('1.-');
  List.Add('2.--');
  List.Add('3.---');

  // Display List contents : note the 0 indexing
  for i := 0 to List.Count-1 do
    Console.WriteLine(List.Item[i]);

  // Reverse the order of the array
  Console.WriteLine;
  Console.WriteLine('Reversing the list order :');
  Console.WriteLine;
  List.Reverse;

  // Display List contents again
  for i := 0 to List.Count-1 do
    Console.WriteLine(List.Item[i]);

  Console.Readline;
end.
Show full unit code
  0.
  1.-
  2.--
  3.---
  
  Reversing the list order :
  
  3.---
  2.--
  1.-
  0.
Reversing just a subset of array elements
program Project1;
{$APPTYPE CONSOLE}

uses
  System.Collections;

var
  List : System.Collections.ArrayList;
  i    : Integer;

begin
  // Create our array list object
  List := ArrayList.Create;

  // Fill it
  List.Add('0.');
  List.Add('1.-');
  List.Add('2.--');
  List.Add('3.---');

  // Display List contents : note the 0 indexing
  for i := 0 to List.Count-1 do
    Console.WriteLine(List.Item[i]);

  // Reverse the middle 2 elements of the array
  Console.WriteLine;
  Console.WriteLine('Reversing the middle 2 elements :');
  Console.WriteLine;
  List.Reverse(1, 2);

  // Display List contents again
  for i := 0 to List.Count-1 do
    Console.WriteLine(List.Item[i]);

  Console.Readline;
end.
Show full unit code
  0.
  1.-
  2.--
  3.---
  
  Reversing the middle 2 elements :
  
  0.
  2.--
  1.-
  3.---
 
 
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