procedure TForm2.SpeedButton1Click(Sender: TObject);
var tmplist:TStringList;
    tmpstream:TFileStream;
begin
  tmplist:=TStringList.Create ;
  if OpenDialog1.Execute then
     begin
     tmpstream:=TFileStream.Create(OpenDialog1.FileName,fmOpenRead);
     tmpstream.Position:=0;
     tmplist.LoadFromStream(tmpstream);
     showmessage(inttostr(tmplist.Count ));
     end;
  tmplist.Free ;
  tmpstream.Free ;
end;
//将tmplist换成memo1,试试