private void EditStudent_Click(object sender, RoutedEventArgs e)
        {
            EditStudentWindow editStudentInfo = new EditStudentWindow();

            editStudentInfo.ShowDialog();
            this.Close();
            //show edit student window
        }
        private void closebtn_Click(object sender, RoutedEventArgs e)
        {
            //close window
            EditStudentWindow editStudentWindow = new EditStudentWindow();

            editStudentWindow.Show();
            Close();
        }