private void Subjects_Click(object sender, RoutedEventArgs e)
        {
            TeacherSubject ts = new TeacherSubject(int.Parse(teacher.Id.ToString()));

            ts.Show();
            this.Close();
        }
 private void Button_Click(object sender, RoutedEventArgs e)
 {
     try
     {
         TeacherSubject ts = new TeacherSubject(idTeacher);
         ts.Show();
         this.Close();
     }
     catch
     {
         MessageBox.Show("Something happened \nCommunicate with the Suport department \[email protected]");
     }
 }