title: RegEx force quantifier to be valid
body: <p>I am struggling to get my regex validation for name initials to work.</p>
  
  <p>I have the following code:</p>
  
  <pre><code>// S.P. of Sp.A. 
  string voorletters = "S.P.aAa"; // This should be invalid
  string regexPattern = "^([A-Z]{1}[.]|[A-Z]{1}[a-z]{1,}[.])*";
  var isMatch = Regex.IsMatch(voorletters, regexPattern);
  </code></pre>
  
  <p>The following example should be invalid, but does match and therefore goes through.
  <a href="http://regexhero.net/tester/?id=439e7c6e-ce74-4b5a-ac60-d8abeee69675" rel="nofollow">http://regexhero.net/tester/?id=439e7c6e-ce74-4b5a-ac60-d8abeee69675</a></p>
  
  <p>How can i force the quantifiers (*) for validation?</p>