Классы и их свойства

unit Unit1;
 
interface
 
uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, 
 
Controls, Forms,
  Dialogs, Buttons, StdCtrls, ExtCtrls;
 
type TAnimal = class(TObject)
      private
        Name: string;
      public
        String GetName();
        function TellMe: string; virtual; abstract;
        property TheName: string read GetName;
        constructor Create(AName: string);overload;
        constructor Create; overload;
        destructor Destroy;override;
      end;
 
type THuman = class(TAnimal)
   public
   function TellMe: string; override;
   end;
type TDog = class(TAnimal)
   public
   function TellMe: string; override;
   end;
type TFish = class(TAnimal)
   public
   function TellMe: string; override;
   end;
type TCat = class(TAnimal)
      public
         function TellMe: string; override;
         procedure SetName(AName: string);
         property TheName: string read GetName write SetName;
      end;
 
type
  TForm1 = class(TForm)
    SpeedButton1: TSpeedButton;
    SpeedButton2: TSpeedButton;
    SpeedButton3: TSpeedButton;
    Edit1: TEdit;
    WhoRG: TRadioGroup;
    Label1: TLabel;
    SpeedButton4: TSpeedButton;
    procedure FormCreate(Sender: TObject);
    procedure SpeedButton1Click(Sender: TObject);
    procedure SpeedButton2Click(Sender: TObject);
    procedure SpeedButton3Click(Sender: TObject);
    procedure FormDestroy(Sender: TObject);
    procedure WhoRGClick(Sender: TObject);
    procedure SpeedButton4Click(Sender: TObject);
  private
  procedure Say(Animal:TAnimal);
    { Private declarations }
  public
    { Public declarations }
  end;
 
var
  Form1: TForm1;
 
implementation
 
var
    Human:THuman;
    Dog:TDog;
    Cat:TCat;
    Fish:TFish;
 
constructor TAnimal.Create;
begin
  Name := 'Атсыз';
end;
 
constructor TAnimal.Create(AName: string);
begin
  Name := AName;
end;
 
destructor TAnimal.Destroy;
begin
  ShowMessage(Self.TheName+ ' жойылды!');
  inherited Destroy;
end;
 
{$R *.dfm}
 
function TFish.TellMe;
begin
  Result := 'Золотинка';
end;
 
function THuman.TellMe;
begin
  Result := TheName;
end;
 
function TDog.TellMe;
begin
  Result := 'Гав-Гав!';
end;
 
function TCat.TellMe;
begin
  Result := 'Мяу-мяу!';
end;
 
procedure TForm1.FormCreate(Sender: TObject);
begin
  Human := THuman.Create('Дэниел');
  SpeedButton1.Caption := Human.TheName;
  Dog := TDog.Create('Пушок');
  SpeedButton2.Caption := Dog.TheName;
  Cat := TCat.Create('Барсик');
  SpeedButton3.Caption :=  Cat.TheName;
  Fish := TFish.Create('Золотинка');
  SpeedButton4.Caption :=  Fish.TheName;
end;
 
function TAnimal.GetName;
begin
  Result := Name;
end;
 
procedure TCat.SetName(AName: string);
begin
  Name := AName;
end;
 
procedure TForm1.SpeedButton1Click(Sender: TObject);
begin
  Human.Destroy;
  Human := THuman.Create(Edit1.Text);
  SpeedButton1.Caption := Human.TheName;
end;
 
procedure TForm1.SpeedButton2Click(Sender: TObject);
begin
  Dog.Destroy;
  Dog := TDog.Create(Edit1.Text);
  SpeedButton2.Caption := Dog.TheName;
end;
 
procedure TForm1.SpeedButton3Click(Sender: TObject);
begin
  Cat.Destroy;
  Cat := TCat.Create(Edit1.Text);
  SpeedButton3.Caption := Cat.TheName;
end;
 
procedure TForm1.FormDestroy(Sender: TObject);
begin
   Human.Free;
   Dog.Free;
   Cat.Free;
   Fish.free;
end;
 
procedure TForm1.Say(Animal: TAnimal);
begin
Label1.Caption := Animal.TellMe;
end;
 
procedure TForm1.WhoRGClick(Sender: TObject);
begin
 case  WhoRg.ItemIndex of
   0: Say(Human);
   1: Say(Dog);
   2: Say(Cat);
   3: Say(Fish);
  end;
end;
 
procedure TForm1.SpeedButton4Click(Sender: TObject);
begin
  Fish.Destroy;
  Fish := Tfish.Create(Edit1.Text);
  SpeedButton4.Caption := fish.TheName;
end;
 
end.