title: regular expression: extract last 2 characters
body: <p>what is the best way to extract last 2 characters of a string using regular expression.</p>
  
  <p>For example, I want to extract state code from the following</p>
  
  <p>"A_IL"</p>
  
  <p>I want to extract IL as string..</p>
  
  <p>please provide me C# code on how to get it..</p>
  
  <pre><code>string fullexpression = "A_IL";
  string StateCode = some regular expression code....
  </code></pre>
  
  <p>thanks</p>