unit Unit1;

interface

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls;

type
  TForm1 = class(TForm)
    DOLAR: TEdit;
    Button1: TButton;
    REAL: TEdit;
    Label1: TLabel;
    Label2: TLabel;
    COMPRA: TButton;
    MSG: TLabel;
    procedure Button1Click(Sender: TObject);
    procedure COMPRAClick(Sender: TObject);


  private
    { Private declarations }
  public

    { Public declarations }
  end;

var
  Form1: TForm1;
  VARREAL : REAL;
  VARNOME : STRING;







implementation

{$R *.dfm}



procedure TForm1.Button1Click(Sender: TObject);
begin

 IF DOLAR.Text = ''  then
   BEGIN
    SHOWMESSAGE('DIGITE VALOR EM DOLAR');
   END

 ELSE
   BEGIN
    COMPRA.Enabled := TRUE;
    VARREAL := STRTOFLOAT(DOLAR.Text) * 3.9 ;
    REAL.Text := FLOATTOSTR(VARREAL);


   END;




end;





procedure TForm1.COMPRAClick(Sender: TObject);
begin

 VARNOME := INPUTBOX('NOME','DIGITE SEU NOME','');

 if (VARNOME <> '') AND  (DOLAR.Text <> '0') THEN
   MSG.CAPTION := 'PARABENS ' + VARNOME + ' , VOCE COMPROU ' + DOLAR.Text + ' DOLAR(ES)'
 ELSE
   SHOWMESSAGE ('FALTA NOME OU DOLAR TEM QUE SER > 0');

 end;

end.