private void deleteButton_Click(object sender, RoutedEventArgs e)
{
YesNoWindow yy = new YesNoWindow("Do you want to delete this task ?");
yy.ShowDialog();
if (yy.ans == true)
{
bolayer.task_delete(tasknow);
ftp.deletefile(tasknow.folder);
bolayer.load_task_form_server();
}
}