Result := True;
        break; { found a string with non-ASCII chars (> 127) }
      end;
    end;
  end;
  {$ENDIF}

begin
  inherited DefineProperties(Filer); { Handles main 'Strings' property.' }
  Filer.DefineProperty('WideStrings', ReadData, nil, False);
  Filer.DefineProperty('WideStringsW', ReadDataUTF8, nil, False);
  {$IFDEF COMPILER_7_UP}
  Filer.DefineProperty('WideStrings_UTF7', ReadDataUTF7, WriteDataUTF7, False);
  {$ELSE}
  Filer.DefineProperty('WideStrings_UTF7', ReadDataUTF7, WriteDataUTF7, DoWrite and DoWriteAsUTF7);
  {$ENDIF}
end;

procedure TTntStrings.LoadFromFile(const FileName: WideString);
var
  Stream: TStream;
begin
  Stream := TTntFileStream.Create(FileName, fmOpenRead or fmShareDenyWrite);
  try
    FLastFileCharSet := AutoDetectCharacterSet(Stream);
    Stream.Position := 0;
    LoadFromStream(Stream);
  finally
    Stream.Free;
  end;
end;

procedure TTntStrings.LoadFromStream(Stream: TStream);
begin
  LoadFromStream_BOM(Stream, True);
end;

procedure TTntStrings.LoadFromStream_BOM(Stream: TStream; WithBOM: Boolean);
var
  DataLeft: Integer;
  StreamCharSet: TTntStreamCharSet;
  SW: WideString;
  SA: AnsiString;
begin
  BeginUpdate;
  try
    if WithBOM then
      StreamCharSet := AutoDetectCharacterSet(Stream)
    else
      StreamCharSet := csUnicode;
    DataLeft := Stream.Size - Stream.Position;
    if (StreamCharSet in [csUnicode, csUnicodeSwapped]) then
    begin
      // BOM indicates Unicode text stream
      if DataLeft < SizeOf(WideChar) then
        SW := ''
      else begin
        SetLength(SW, DataLeft div SizeOf(WideChar));
        Stream.Read(PWideChar(SW)^, DataLeft);
        if StreamCharSet = csUnicodeSwapped then
          StrSwapByteOrder(PWideChar(SW));
      end;
      SetTextStr(SW);
    end
    else if StreamCharSet = csUtf8 then
    begin
      // BOM indicates UTF-8 text stream
      SetLength(SA, DataLeft div SizeOf(AnsiChar));
      Stream.Read(PAnsiChar(SA)^, DataLeft);
      SetTextStr(UTF8ToWideString(SA));
    end
    else
    begin
      // without byte order mark it is assumed that we are loading ANSI text
      SetLength(SA, DataLeft div SizeOf(AnsiChar));
      Stream.Read(PAnsiChar(SA)^, DataLeft);
      SetTextStr(SA);
    end;
  finally
    EndUpdate;
  end;
end;

procedure TTntStrings.ReadData(Reader: TReader);
begin
  if Reader.NextValue in [vaString, vaLString] then
    SetTextStr(Reader.ReadString) {JCL compatiblity}
  else if Reader.NextValue = vaWString then
    SetTextStr(Reader.ReadWideString) {JCL compatiblity}
  else begin
    BeginUpdate;
    try
      Clear;
      Reader.ReadListBegin;
      while not Reader.EndOfList do
        if Reader.NextValue in [vaString, vaLString] then
          Add(Reader.ReadString) {TStrings compatiblity}
        else
          Add(Reader.ReadWideString);
      Reader.ReadListEnd;
    finally
      EndUpdate;
    end;
  end;
end;

procedure TTntStrings.ReadDataUTF7(Reader: TReader);
begin
  Reader.ReadListBegin;
  if ReaderNeedsUtfHelp(Reader) then
  begin
    BeginUpdate;
    try
      Clear;
      while not Reader.EndOfList do
        Add(UTF7ToWideString(Reader.ReadString))
    finally
      EndUpdate;
    end;
  end else begin
    while not Reader.EndOfList do
      Reader.ReadString; { do nothing with Result }
  end;
  Reader.ReadListEnd;
end;

procedure TTntStrings.ReadDataUTF8(Reader: TReader);
begin
  Reader.ReadListBegin;
  if ReaderNeedsUtfHelp(Reader)
  or (Count = 0){ Legacy support where 'WideStrings' was never written in lieu of WideStringsW }
  then begin
    BeginUpdate;
    try
      Clear;
      while not Reader.EndOfList do
        Add(UTF8ToWideString(Reader.ReadString))
    finally
      EndUpdate;
    end;
  end else begin
    while not Reader.EndOfList do
      Reader.ReadString; { do nothing with Result }
  end;
  Reader.ReadListEnd;
end;

procedure TTntStrings.SaveToFile(const FileName: WideString);
var
  Stream: TStream;
begin
  Stream := TTntFileStream.Create(FileName, fmCreate);
  try
    SaveToStream(Stream);
  finally
    Stream.Free;
  end;
end;

procedure TTntStrings.SaveToStream(Stream: TStream);
begin
  SaveToStream_BOM(Stream, True);
end;

procedure TTntStrings.SaveToStream_BOM(Stream: TStream; WithBOM: Boolean);
// Saves the currently loaded text into the given stream.
// WithBOM determines whether to write a byte order mark or not.
var
  SW: WideString;
  BOM: WideChar;
begin
  if WithBOM then begin
    BOM := UNICODE_BOM;
    Stream.WriteBuffer(BOM, SizeOf(WideChar));
  end;
  SW := GetTextStr;
  Stream.WriteBuffer(PWideChar(SW)^, Length(SW) * SizeOf(WideChar));
end;

procedure TTntStrings.WriteDataUTF7(Writer: TWriter);
var
  I: Integer;
begin
  Writer.WriteListBegin;
  for I := 0 to Count-1 do
    Writer.WriteString(WideStringToUTF7(Get(I)));
  Writer.WriteListEnd;
end;

{ TTntStringList }

destructor TTntStringList.Destroy;
begin
  FOnChange := nil;
  FOnChanging := nil;
  inherited Destroy;
  if FCount <> 0 then Finalize(FList^[0], FCount);
  FCount := 0;
  SetCapacity(0);
end;

function TTntStringList.Add(const S: WideString): Integer;
begin
  Result := AddObject(S, nil);
end;

function TTntStringList.AddObject(const S: WideString; AObject: TObject): Integer;
begin
  if not Sorted then
    Result := FCount
  else
    if Find(S, Result) then
      case Duplicates of
        dupIgnore: Exit;
        dupError: Error(PResStringRec(@SDuplicateString), 0);
      end;
  InsertItem(Result, S, AObject);
end;

procedure TTntStringList.Changed;
begin
  if (not FUpdating) and Assigned(FOnChange) then
    FOnChange(Self);
end;

procedure TTntStringList.Changing;
begin
  if (not FUpdating) and Assigned(FOnChanging) then
    FOnChanging(Self);
end;

procedure TTntStringList.Clear;
begin
  if FCount <> 0 then
  begin
    Changing;
    Finalize(FList^[0], FCount);
    FCount := 0;
    SetCapacity(0);
    Changed;
  end;
end;

procedure TTntStringList.Delete(Index: Integer);
begin
  if (Index < 0) or (Index >= FCount) then Error(PResStringRec(@SListIndexError), Index);
  Changing;
  Finalize(FList^[Index]);
  Dec(FCount);
  if Index < FCount then
    System.Move(FList^[Index + 1], FList^[Index],
      (FCount - Index) * SizeOf(TWideStringItem));
  Changed;
end;

procedure TTntStringList.Exchange(Index1, Index2: Integer);
begin
  if (Index1 < 0) or (Index1 >= FCount) then Error(PResStringRec(@SListIndexError), Index1);
  if (Index2 < 0) or (Index2 >= FCount) then Error(PResStringRec(@SListIndexError), Index2);
  Changing;
  ExchangeItems(Index1, Index2);
  Changed;
end;

procedure TTntStringList.ExchangeItems(Index1, Index2: Integer);
var
  Temp: Integer;
  Item1, Item2: PWideStringItem;
begin
  Item1 := @FList^[Index1];
  Item2 := @FList^[Index2];
  Temp := Integer(Item1^.FString);
  Integer(Item1^.FString) := Integer(Item2^.FString);
  Integer(Item2^.FString) := Temp;
  Temp := Integer(Item1^.FObject);
  Integer(Item1^.FObject) := Integer(Item2^.FObject);
  Integer(Item2^.FObject) := Temp;
end;

function TTntStringList.Find(const S: WideString; var Index: Integer): Boolean;
var
  L, H, I, C: Integer;
begin
  Result := False;
  L := 0;
  H := FCount - 1;
  while L <= H do
  begin
    I := (L + H) shr 1;
    C := CompareStrings(FList^[I].FString, S);
    if C < 0 then L := I + 1 else
    begin
      H := I - 1;
      if C = 0 then
      begin
        Result := True;
        if Duplicates <> dupAccept then L := I;
      end;
    end;
  end;
  Index := L;
end;

function TTntStringList.Get(Index: Integer): WideString;
begin
  if (Index < 0) or (Index >= FCount) then Error(PResStringRec(@SListIndexError), Index);
  Result := FList^[Index].FString;
end;

function TTntStringList.GetCapacity: Integer;
begin
  Result := FCapacity;
end;

function TTntStringList.GetCount: Integer;
begin
  Result := FCount;
end;

function TTntStringList.GetObject(Index: Integer): TObject;
begin
  if (Index < 0) or (Index >= FCount) then Error(PResStringRec(@SListIndexError), Index);
  Result := FList^[Index].FObject;
end;

procedure TTntStringList.Grow;
var
  Delta: Integer;
begin
  if FCapacity > 64 then Delta := FCapacity div 4 else
    if FCapacity > 8 then Delta := 16 else
      Delta := 4;
  SetCapacity(FCapacity + Delta);
end;

function TTntStringList.IndexOf(const S: WideString): Integer;
begin
  if not Sorted then Result := inherited IndexOf(S) else
    if not Find(S, Result) then Result := -1;
end;

function TTntStringList.IndexOfName(const Name: WideString): Integer;
var
  NameKey: WideString;
begin
  if not Sorted then
    Result := inherited IndexOfName(Name)
  else begin
    // use sort to find index more quickly
    NameKey := Name + NameValueSeparator;
    Find(NameKey, Result);
    if (Result < 0) or (Result > Count - 1) then
      Result := -1
    else if CompareStrings(NameKey, Copy(Strings[Result], 1, Length(NameKey))) <> 0 then
      Result := -1
  end;
end;

procedure TTntStringList.Insert(Index: Integer; const S: WideString);
begin
  InsertObject(Index, S, nil);
end;

procedure TTntStringList.InsertObject(Index: Integer; const S: WideString;
  AObject: TObject);
begin
  if Sorted then Error(PResStringRec(@SSortedListError), 0);
  if (Index < 0) or (Index > FCount) then Error(PResStringRec(@SListIndexError), Index);
  InsertItem(Index, S, AObject);
end;

procedure TTntStringList.InsertItem(Index: Integer; const S: WideString; AObject: TObject);
begin
  Changing;
  if FCount = FCapacity then Grow;
  if Index < FCount then
    System.Move(FList^[Index], FList^[Index + 1],
      (FCount - Index) * SizeOf(TWideStringItem));
  with FList^[Index] do
  begin
    Pointer(FString) := nil;
    FObject := AObject;
    FString := S;
  end;
  Inc(FCount);
  Changed;
end;

procedure TTntStringList.Put(Index: Integer; const S: WideString);
begin
  if Sorted then Error(PResStringRec(@SSortedListError), 0);
  if (Index < 0) or (Index >= FCount) then Error(PResStringRec(@SListIndexError), Index);
  Changing;
  FList^[Index].FString := S;
  Changed;
end;

procedure TTntStringList.PutObject(Index: Integer; AObject: TObject);
begin
  if (Index < 0) or (Index >= FCount) then Error(PResStringRec(@SListIndexError), Index);
  Changing;
  FList^[Index].FObject := AObject;
  Changed;
end;

procedure TTntStringList.QuickSort(L, R: Integer; SCompare: TWideStringListSortCompare);
var
  I, J, P: Integer;
begin
  repeat
    I := L;
    J := R;
    P := (L + R) shr 1;
    repeat
      while SCompare(Self, I, P) < 0 do Inc(I);
      while SCompare(Self, J, P) > 0 do Dec(J);
      if I <= J then
      begin
        ExchangeItems(I, J);
        if P = I then
          P := J
        else if P = J then
          P := I;
        Inc(I);
        Dec(J);
      end;
    until I > J;
    if L < J then QuickSort(L, J, SCompare);
    L := I;
  until I >= R;
end;

procedure TTntStringList.SetCapacity(NewCapacity: Integer);
begin
  ReallocMem(FList, NewCapacity * SizeOf(TWideStringItem));
  FCapacity := NewCapacity;
end;

procedure TTntStringList.SetSorted(Value: Boolean);
begin
  if FSorted <> Value then
  begin
    if Value then Sort;
    FSorted := Value;
  end;
end;