title: How do you add an index field to Linq results
body: <p>Lets say I have an array like this:</p>
  
  <pre><code>string [] Filelist = ...
  </code></pre>
  
  <p>I want to create an Linq result where each entry has it's position in the array like this:</p>
  
  <pre><code>var list = from f in Filelist
      select new { Index = (something), Filename = f};
  </code></pre>
  
  <p>Index to be 0 for the 1st item, 1 for the 2nd, etc.</p>
  
  <p>What should I use for the expression Index= ?</p>