unit WideStrings;

interface

uses classes,SysUtils;

type

  TWString = record
    WString: WideString;
  end;

  TWideStrings = class
  private
    FWideStringList: TList;
    function Get(Index: Integer): WideString;
    procedure Put(Index: Integer; const S: WideString);
  public
    constructor Create;
    destructor Destroy; override;
    function  Count: Integer;
    procedure Clear;
    function Add(const S: WideString): Integer;
    function IndexOf(const S: WideString): Integer;
    function IndexOfIgnoreCase(const S: WideString): Integer;
    procedure Insert(Index: Integer; const S: WideString);
    property Strings[Index: Integer]: WideString read Get write Put; default;
  end;

const
  SWideStringOutOfBounds = 'WideString index out of bounds';

implementation

{ TWideStrings implementation }
constructor TWideStrings.Create;
begin
  FWideStringList := TList.Create;
end;

destructor TWideStrings.Destroy;
var
  Index: Integer;
  PWStr: ^TWString;
begin
  for Index := 0 to FWideStringList.Count-1 do
  begin
    PWStr := FWideStringList.Items[Index];
    if PWStr <> nil then
      Dispose(PWStr);
  end;
  FWideStringList.Free;
  inherited Destroy;
end;

function TWideStrings.Get(Index: Integer): WideString;
var
  PWStr: ^TWString;
begin
  Result := '';
  if ( (Index >= 0) and (Index < FWideStringList.Count) ) then
  begin
    PWStr := FWideStringList.Items[Index];
    if PWStr <> nil then
      Result := PWStr^.WString;
  end;
end;

procedure TWideStrings.Put(Index: Integer; const S: WideString);
begin
  Insert(Index,S);
end;

function TWideStrings.Add(const S: WideString): Integer;
var
  PWStr: ^TWString;
begin
  New(PWStr);
  PWStr^.WString := S;
  Result := FWideStringList.Add(PWStr);
end;

function TWideStrings.IndexOfIgnoreCase(const S: WideString): Integer;
var
  Index: Integer;
  PWStr: ^TWString;
begin
  Result := -1;
  for Index := 0 to FWideStringList.Count -1 do
  begin
    PWStr := FWideStringList.Items[Index];
    if PWStr <> nil then
    begin
      if SameText(S, PWStr^.WString) then
      begin
        Result := Index;
        break;
      end;
    end;
  end;
end;

function TWideStrings.IndexOf(const S: WideString): Integer;
var
  Index: Integer;
  PWStr: ^TWString;
begin
  Result := -1;
  for Index := 0 to FWideStringList.Count -1 do
  begin
    PWStr := FWideStringList.Items[Index];
    if PWStr <> nil then
    begin
      if S = PWStr^.WString then
      begin
        Result := Index;
        break;
      end;
    end;
  end;
end;

function TWideStrings.Count: Integer;
begin
  Result := FWideStringList.Count;
end;

procedure TWideStrings.Clear;
var
  Index: Integer;
  PWStr: ^TWString;
begin
  for Index := 0 to FWideStringList.Count-1 do
  begin
    PWStr := FWideStringList.Items[Index];
    if PWStr <> nil then
      Dispose(PWStr);
  end;
  FWideStringList.Clear;
end;

procedure TWideStrings.Insert(Index: Integer; const S: WideString);
var
  PWStr: ^TWString;
begin
  if((Index < 0) or (Index > FWideStringList.Count)) then
    raise Exception.Create(SWideStringOutofBounds);
  if Index < FWideStringList.Count then
  begin
    PWStr := FWideStringList.Items[Index];
    if PWStr <> nil then
      PWStr.WString := S;
  end
  else
    Add(S);
end;

end.

本文来源：http://blog.csdn.net/Raoxk/archive/2007/08/27/1761259.aspx