Erweitern einer Klasse um eine Methode

[md_mse]

Ich würde es z.B. so lösen:

Delphi-Quellcode:

type

  THuman = class;

  TSpeakMethod = procedure(HumanObject: THuman) of object;

  THuman = class
    FProp1: Integer;
    FProp2: Byte;
    FSpeakMethod: TSpeakMethod;
  public
    procedure OnSpeak;
    property SpeakMethod: TSpeakMethod read FSpeakMethod write FSpeakMethod;
  end;

implementation

{ THuman }

procedure THuman.OnSpeak;
begin
  if (@FSpeakMethod <> nil) then
    FSpeakMethod(Self);
end;