private void StudentsDataGrid_MouseDoubleClick(object sender, MouseButtonEventArgs e)
{
Student student = (Student)StudentsDataGrid.SelectedItem;
DetailedBox win = new DetailedBox("Modify", student, this);
win.Show();
}
private void AddButton_Click(object sender, RoutedEventArgs e)
{
DetailedBox win = new DetailedBox("Add", null, this);
win.Show();
}