private void delete_button_Click(object sender, RoutedEventArgs e)
{
if (deleteCB.SelectedItem == null)
{
MessageBox.Show("Please select an item to delete.");
}
else
{
FileReadWrite file = new FileReadWrite();
oldTask = student.TaskList[deleteCB.SelectedIndex];
student.DeleteTask(deleteCB.SelectedIndex);
file.DeleteTaskToFile(student, oldTask);
homeScreen hs = new homeScreen(student);
this.Close();
hs.Show();
}
}