title: how to get one part of the string
body: <p>I have a string 
  eg.</p>
  
  <pre><code>string a =  "OU=QALevel1,DC=CopTest,DC=copiun2,DC=com";
  </code></pre>
  
  <p>now i want my temp string to have the value</p>
  
  <pre><code> tempString = "DC=CopTest,DC=copiun2,DC=com"
  </code></pre>
  
  <p>I need to remove all occurrences of the <code>OU</code> value pairs from the strings. These <em>always</em> appear first in the string.</p>