title: convert variable to constant
body: <p>Can seems to be strange, but is there a way to declare or convert variable to constante something like :</p>
  
  <pre><code>string myVariable = "MyString";
  const string myConstant = myVariable ;
  </code></pre>
  
  <p>I need this to answer to my problem:
  <a href="https://stackoverflow.com/questions/25931201/linq-to-sql-startwith-performance-indexed-columns">linq to sql startwith performance indexed columns</a></p>
  
  <p>thanks</p>