private void button4_Click(object sender, EventArgs e)
        {
            backend.MovieList movlis = new backend.MovieList();

            //load the list from listview
            movlis.ListOfMovies = retrive();

            backend.json.json.JsonSerial(movlis.ListOfMovies, tbJsonSave.Text);
            tbfiletoServer.Text = tbJsonSave.Text;
        }
        // load from file
        private void button3_Click(object sender, EventArgs e)
        {
            //create excel save handler
            backend.ExcelHandler handler = new backend.ExcelHandler();
            //create List of movies
            backend.MovieList movlis = new backend.MovieList();

            //load the list from listview
            movlis.ListOfMovies = retrive();
            try
            {
                //save to file
                handler.ExportExcel(movlis, tbSaveExcel.Text);
            }
            catch (Exception x)
            {
                MessageBox.Show("fileName Bad" + x);
            }
        }