title: Get string that follows second-last occurrence of character/string
body: <p>I have an unusual project in which I need to retrieve the text after the second-last occurrence of the character "\", effectively giving me the last two directories in the following example strings:</p>
  
  <ul>
  <li>D:\Archive Directory\2015-12-31 PM\SerialNo_01</li>
  <li>D:\Archive Directory\2016-01-01\SerialNo_02</li>
  <li>D:\Archive Directory\January 2016\SerialNo_03</li>
  </ul>
  
  <p>The desired result is, respectively:</p>
  
  <ul>
  <li>2015-12-31 PM\SerialNo_01 </li>
  <li>2016-01-01\SerialNo_02</li>
  <li>January 2016\SerialNo_03</li>
  </ul>
  
  <p>I'd like to do this as cleanly as possible and preferably in one line of code for each string. </p>
  
  <p><em>This question is being answered by me after finding nothing on Stack Overflow about finding the second-last occurrence (or, for that matter, any Nth occurrence going backwards) of a string or character within a string in c#. If the community finds this question is duplicated or feels it is too obscure a case, I am willing to remove it.</em></p>
  
  <p><strong>Edit:</strong> Clarified that I don't need to do this as a list of strings; they will be run one at a time. I'm dynamically adding them as radio button controls to a form. </p>