private void OnExportToExcel()
        {
            UpdateStatus("Экспорт...");
            var dlg = new SaveFileDialog
            {
                FileName   = "Расписание",
                DefaultExt = ".xlsx",
                Filter     = "Расписание|*.xlsx"
            };
            var result = dlg.ShowDialog();

            if (result == true)
            {
                ImportExportSchedule.Export(Project.Schedule, dlg.FileName);
            }
            UpdateStatus("Экспорт выполнен");
        }
        private void OnImportFromExcel()
        {
            var dlg = new OpenFileDialog
            {
                FileName   = "Расписание",
                DefaultExt = ".xlsx",
                Filter     = "Расписание|*.xlsx"
            };
            var result = dlg.ShowDialog();

            if (result == true)
            {
                var schedule = ImportExportSchedule.Import(dlg.FileName);
                SetNewProject(new ScheduleProject {
                    Schedule = schedule
                });
            }
            UpdateStatus("Импорт выполнен");
        }