procedure TForm1.Button1Click(Sender: TObject);
begin
   form2:=tform2.create(self);
   form2.showmodal;
end;
//
procedure TForm2.FormDblClick(Sender: TObject);
begin
    modalresult:=mrok;
end;
//Form2没有free
procedure TForm1.Button2Click(Sender: TObject);
begin
    form2.showmodal;
end;