title: How to get only letters from a string in C#?
body: <p>I have a string and need the letters from said string.</p>
  
  <pre><code>string s = "EMA123_33";    // I need "EMA"
  string s = "EMADRR123_33"; // I need "EMADRR"
  </code></pre>
  
  <p>I am using C# in Visual Studio 2008.</p>