Default array-property

What is translated > Properties > Default array-property

If a class has a default property, you can access that property in Object-Pascal with the abbreviation object[index], which is equivalent to object.property[index]. For C++Builder the translated code looks like:

type

  // Class with Indexed properties

  TRectangle = class

  private

    fCoords: array[0..3] of Longint;

    function  GetCoord(Index: Integer): Longint;

    procedure SetCoord(Index: Integer; Value: Longint);

  public

    property Coords[Index: Integer] : Longint

             read GetCoord write SetCoord; Default;

  end;

->

C++Builder

class TRectangle : public TObject

{

  typedef TObject inherited;

private:

  int fCoords[4/*# range 0..3*/];

  int __fastcall GetCoord(int Index);

  void __fastcall SetCoord(int Index, int Value);

public:

  __property int Coords[int Index] = { read = GetCoord, write = SetCoord/*# default */ };

public:

  __fastcall TRectangle() {}

};

Other compilers

class TRectangle : public TObject

{

  typedef TObject inherited;

private:

  int fCoords[4/*# range 0..3*/];

  int GetCoord(int Index);

  void SetCoord(int Index, int Value);

public:

  /*property Coords [Index: integer]: int read GetCoord write SetCoord default ;*/

  int ReadPropertyCoords(int Index) { return GetCoord(Index);}

  void WritePropertyCoords(int Index, int Value){SetCoord(Index, Value);}int operator[ ](int Index) { return

  GetCoord(Index);  }

public:

  TRectangle() {}

};

If there is an instance ot TRectangle the array can be accessed in Delphi simply by rect [i]. For C++Builder this becomes to:

rect->Coords[i]

and for other compilers:

  rect->WritePropertyCoords(i, 0);

  ... = rect->ReadPropertyCoords(i);

This page belongs to the DelphiXE2Cpp11 Documentation