[NumLock]

exe:

Код:

type
  TForm1 = class(TForm)
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
    procedure CB(Sender: TObject);
  end;

function ShowForm(Sender: TNotifyEvent): Integer; external 'Project2.dll';

procedure TForm1.Button1Click(Sender: TObject);
begin
  ShowForm(CB);
end;

procedure TForm1.CB(Sender: TObject);
begin
  ShowMessage(TEdit(TForm(Sender).FindComponent('Edit1')).Text);
end;

dll:

Код:

library Project2;

uses
  Forms,
  SysUtils,
  Classes,
  Unit2 in 'Unit2.pas' {Form2};

{$R *.res}

function ShowForm(Sender: TNotifyEvent): Integer;
begin
  Form2:=TForm2.Create(Application);
  Form2.CB:=Sender;
  Result:=Form2.ShowModal;
  Form2.Free;
end;

exports
  ShowForm;

begin
end.

dll form:

Код:

type
  TForm2 = class(TForm)
    Button1: TButton;
    Label1: TLabel;
    Edit1: TEdit;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
    CB: TNotifyEvent;
  end;

procedure TForm2.Button1Click(Sender: TObject);
begin
  CB(Self);
end;