Tópico: passar valores de variaveis de um form para outro no delphi 7

procedure Tfrmctpagartitulos.bbinclusaoClick(Sender: TObject);
begin
  with Tfrmctpagartitulos2.Create(Self) do
  try
    numero_nota_fiscal := 00001;
    serie_nota_fiscal : U;
    frmctpagartitulos2.ShowModal;
  finally
    FreeAndNil(frmctpagartitulos2);
  end;

// Unit do form1
unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, FMTBcd;

type
  TForm1 = class(TForm)
    btn1: TButton;
    procedure btn1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

uses Unit2;

{$R *.dfm}

procedure TForm1.btn1Click(Sender: TObject);
begin
     try
       Form2 := TForm2.Create(self);
       //Passo o valo 001 para variável que está no form2
       campo := 001;
       Form2.ShowModal;
     finally
        FreeAndNil(form2);
     end;
end;

end.

//Unit do form2
unit Unit2;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;

type
  TForm2 = class(TForm)
    btn1: TButton;
    procedure btn1Click(Sender: TObject);
    procedure FormShow(Sender: TObject);
  private
    { Private declarations }
  public

  end;

var
  Form2: TForm2;
  campo: Integer; // Declaração da variável

implementation

{$R *.dfm}

procedure TForm2.btn1Click(Sender: TObject);
begin
    ShowMessage(IntToStr(campo));
end;

procedure TForm2.FormShow(Sender: TObject);
begin
    ShowMessage(IntToStr(campo));
end;

end.