title: Sort list after lastname and than after firstname in C#
body: <p>How can I enhance my following function</p>
  
  <pre><code>personList.Sort (delegate (Person firstPerson, Person secondPerson) {
      return firstPerson.Lastname.CompareTo (secondPerson.Lastname);
  });
  </code></pre>
  
  <p>to first sort after last name and than after first name?</p>