type
  rec1 = record
    A, B: string;
  end;
  rec1Arr = array of rec1;

  rec2 = record
    C, D: string;
  end;
  rec2Arr = array of rec2;

  rec3 = record
    E, F: string;
  end;
  rec3Arr = array of rec3;

  TMyRec = record
    type
      TAll = record
        A,B,C,D,E,F : string;
      end;
  private
    function GetAll(Index: integer): TAll;
    procedure SetAll(Index: integer; const Value: TAll);
  public
    R1: rec1Arr;
    R2: rec2Arr;
    R3: rec3Arr;

    property All[Index: integer]: TAll read GetAll write SetAll; default;
  end;

{ TMyRec }

function TMyRec.GetAll(Index: integer): TAll;
begin
  Result.A:=R1[index].A;
  Result.B:=R1[index].B;
  Result.C:=R2[index].C;
  Result.D:=R2[index].D;
  Result.E:=R3[index].E;
  Result.F:=R3[index].F;
end;

procedure TMyRec.SetAll(Index: integer; const Value: TAll);
begin
  if Length(R1)<=Index then SetLength(R1,Index+1);
  if Length(R2)<=Index then SetLength(R2,Index+1);
  if Length(R3)<=Index then SetLength(R3,Index+1);
  R1[index].A:=Value.A;
  R1[index].B:=Value.B;
  R2[index].C:=Value.C;
  R2[index].D:=Value.D;
  R3[index].E:=Value.E;
  R3[index].F:=Value.F;
end;


procedure Test;
var
  Arr : TMyRec;
  Rec : TMyRec.TAll;
begin
  Rec.A:='1';
  Rec.B:='2';
  Rec.C:='3';
  Rec.D:='4';
  Rec.E:='5';
  Rec.F:='6';
  Arr[1]:=Rec;
  Writeln(Arr[1].A,',',Arr[1].B,',',Arr[1].C,',',Arr[1].D,',',Arr[1].E,',',Arr[1].F);
end;